diff options
Diffstat (limited to 'src/libexpr')
| -rw-r--r-- | src/libexpr/Makefile.am | 23 | ||||
| -rw-r--r-- | src/libexpr/attr-path.cc | 53 | ||||
| -rw-r--r-- | src/libexpr/attr-path.hh | 4 | ||||
| -rw-r--r-- | src/libexpr/common-opts.cc | 14 | ||||
| -rw-r--r-- | src/libexpr/common-opts.hh | 2 | ||||
| -rw-r--r-- | src/libexpr/eval.cc | 1450 | ||||
| -rw-r--r-- | src/libexpr/eval.hh | 324 | ||||
| -rw-r--r-- | src/libexpr/expr-to-xml.cc | 186 | ||||
| -rw-r--r-- | src/libexpr/expr-to-xml.hh | 16 | ||||
| -rw-r--r-- | src/libexpr/get-drvs.cc | 207 | ||||
| -rw-r--r-- | src/libexpr/get-drvs.hh | 22 | ||||
| -rw-r--r-- | src/libexpr/lexer.l | 48 | ||||
| -rw-r--r-- | src/libexpr/nixexpr-ast.def | 97 | ||||
| -rw-r--r-- | src/libexpr/nixexpr.cc | 538 | ||||
| -rw-r--r-- | src/libexpr/nixexpr.hh | 288 | ||||
| -rw-r--r-- | src/libexpr/parser.hh | 7 | ||||
| -rw-r--r-- | src/libexpr/parser.y | 454 | ||||
| -rw-r--r-- | src/libexpr/primops.cc | 828 | ||||
| -rw-r--r-- | src/libexpr/symbol-table.hh | 81 | ||||
| -rw-r--r-- | src/libexpr/value-to-xml.cc | 159 | ||||
| -rw-r--r-- | src/libexpr/value-to-xml.hh | 17 |
21 files changed, 2513 insertions, 2305 deletions
diff --git a/src/libexpr/Makefile.am b/src/libexpr/Makefile.am index e16600fbf1..e7228e1835 100644 --- a/src/libexpr/Makefile.am +++ b/src/libexpr/Makefile.am @@ -2,27 +2,25 @@ pkglib_LTLIBRARIES = libexpr.la libexpr_la_SOURCES = \ nixexpr.cc eval.cc primops.cc lexer-tab.cc parser-tab.cc \ - get-drvs.cc attr-path.cc expr-to-xml.cc common-opts.cc \ + get-drvs.cc attr-path.cc value-to-xml.cc common-opts.cc \ names.cc pkginclude_HEADERS = \ nixexpr.hh eval.hh parser.hh lexer-tab.hh parser-tab.hh \ - get-drvs.hh attr-path.hh expr-to-xml.hh common-opts.hh \ - names.hh nixexpr-ast.hh + get-drvs.hh attr-path.hh value-to-xml.hh common-opts.hh \ + names.hh symbol-table.hh libexpr_la_LIBADD = ../libutil/libutil.la ../libstore/libstore.la \ ../boost/format/libformat.la -BUILT_SOURCES = nixexpr-ast.cc nixexpr-ast.hh \ +BUILT_SOURCES = \ parser-tab.hh lexer-tab.hh parser-tab.cc lexer-tab.cc -EXTRA_DIST = lexer.l parser.y nixexpr-ast.def nixexpr-ast.cc +EXTRA_DIST = lexer.l parser.y AM_CXXFLAGS = \ - -I$(srcdir)/.. ${aterm_include} \ + -I$(srcdir)/.. \ -I$(srcdir)/../libutil -I$(srcdir)/../libstore -AM_CFLAGS = \ - ${aterm_include} # Parser generation. @@ -34,15 +32,6 @@ lexer-tab.cc lexer-tab.hh: lexer.l $(flex) --outfile lexer-tab.cc --header-file=lexer-tab.hh $(srcdir)/lexer.l -# ATerm helper function generation. - -nixexpr-ast.cc nixexpr-ast.hh: ../aterm-helper.pl nixexpr-ast.def - $(perl) $(srcdir)/../aterm-helper.pl nixexpr-ast.hh nixexpr-ast.cc < $(srcdir)/nixexpr-ast.def - - -CLEANFILES = - - # SDF stuff (not built by default). nix.tbl: nix.sdf sdf2table -m Nix -s -i nix.sdf -o nix.tbl diff --git a/src/libexpr/attr-path.cc b/src/libexpr/attr-path.cc index e8e4c050cc..0660ba1c1e 100644 --- a/src/libexpr/attr-path.cc +++ b/src/libexpr/attr-path.cc @@ -1,23 +1,12 @@ #include "attr-path.hh" -#include "nixexpr-ast.hh" #include "util.hh" namespace nix { -bool isAttrs(EvalState & state, Expr e, ATermMap & attrs) -{ - e = evalExpr(state, e); - ATermList dummy; - if (!matchAttrs(e, dummy)) return false; - queryAllAttrs(e, attrs, false); - return true; -} - - -Expr findAlongAttrPath(EvalState & state, const string & attrPath, - const ATermMap & autoArgs, Expr e) +void findAlongAttrPath(EvalState & state, const string & attrPath, + const Bindings & autoArgs, Expr * e, Value & v) { Strings tokens = tokenizeString(attrPath, "."); @@ -25,8 +14,10 @@ Expr findAlongAttrPath(EvalState & state, const string & attrPath, Error(format("attribute selection path `%1%' does not match expression") % attrPath); string curPath; + + state.mkThunk_(v, e); - for (Strings::iterator i = tokens.begin(); i != tokens.end(); ++i) { + foreach (Strings::iterator, i, tokens) { if (!curPath.empty()) curPath += "."; curPath += *i; @@ -38,7 +29,10 @@ Expr findAlongAttrPath(EvalState & state, const string & attrPath, if (string2Int(attr, attrIndex)) apType = apIndex; /* Evaluate the expression. */ - e = evalExpr(state, autoCallFunction(evalExpr(state, e), autoArgs)); + Value vTmp; + state.autoCallFunction(autoArgs, v, vTmp); + v = vTmp; + state.forceValue(v); /* It should evaluate to either an attribute set or an expression, according to what is specified in the @@ -46,36 +40,31 @@ Expr findAlongAttrPath(EvalState & state, const string & attrPath, if (apType == apAttr) { - ATermMap attrs; - - if (!isAttrs(state, e, attrs)) + if (v.type != tAttrs) throw TypeError( format("the expression selected by the selection path `%1%' should be an attribute set but is %2%") - % curPath % showType(e)); - - e = attrs.get(toATerm(attr)); - if (!e) - throw Error(format("attribute `%1%' in selection path `%2%' not found") % attr % curPath); + % curPath % showType(v)); + Bindings::iterator a = v.attrs->find(state.symbols.create(attr)); + if (a == v.attrs->end()) + throw Error(format("attribute `%1%' in selection path `%2%' not found") % attr % curPath); + v = a->second.value; } else if (apType == apIndex) { - ATermList es; - if (!matchList(e, es)) + if (v.type != tList) throw TypeError( format("the expression selected by the selection path `%1%' should be a list but is %2%") - % curPath % showType(e)); + % curPath % showType(v)); - e = ATelementAt(es, attrIndex); - if (!e) - throw Error(format("list index %1% in selection path `%2%' not found") % attrIndex % curPath); - + if (attrIndex >= v.list.length) + throw Error(format("list index %1% in selection path `%2%' is out of range") % attrIndex % curPath); + + v = *v.list.elems[attrIndex]; } } - - return e; } diff --git a/src/libexpr/attr-path.hh b/src/libexpr/attr-path.hh index 7abaa83a01..33587e5ede 100644 --- a/src/libexpr/attr-path.hh +++ b/src/libexpr/attr-path.hh @@ -10,8 +10,8 @@ namespace nix { -Expr findAlongAttrPath(EvalState & state, const string & attrPath, - const ATermMap & autoArgs, Expr e); +void findAlongAttrPath(EvalState & state, const string & attrPath, + const Bindings & autoArgs, Expr * e, Value & v); } diff --git a/src/libexpr/common-opts.cc b/src/libexpr/common-opts.cc index 9e3f8f9614..5a4856568b 100644 --- a/src/libexpr/common-opts.cc +++ b/src/libexpr/common-opts.cc @@ -9,7 +9,7 @@ namespace nix { bool parseOptionArg(const string & arg, Strings::iterator & i, const Strings::iterator & argsEnd, EvalState & state, - ATermMap & autoArgs) + Bindings & autoArgs) { if (arg != "--arg" && arg != "--argstr") return false; @@ -19,11 +19,13 @@ bool parseOptionArg(const string & arg, Strings::iterator & i, string name = *i++; if (i == argsEnd) throw error; string value = *i++; - - Expr e = arg == "--arg" - ? parseExprFromString(state, value, absPath(".")) - : makeStr(value); - autoArgs.set(toATerm(name), e); + + Value & v(autoArgs[state.symbols.create(name)].value); + + if (arg == "--arg") + state.mkThunk_( v, parseExprFromString(state, value, absPath("."))); + else + mkString(v, value); return true; } diff --git a/src/libexpr/common-opts.hh b/src/libexpr/common-opts.hh index fb9659cdc5..80298ce55d 100644 --- a/src/libexpr/common-opts.hh +++ b/src/libexpr/common-opts.hh @@ -9,7 +9,7 @@ namespace nix { /* Some common option parsing between nix-env and nix-instantiate. */ bool parseOptionArg(const string & arg, Strings::iterator & i, const Strings::iterator & argsEnd, EvalState & state, - ATermMap & autoArgs); + Bindings & autoArgs); } diff --git a/src/libexpr/eval.cc b/src/libexpr/eval.cc index cd9c645947..69632eb37e 100644 --- a/src/libexpr/eval.cc +++ b/src/libexpr/eval.cc @@ -4,9 +4,10 @@ #include "util.hh" #include "store-api.hh" #include "derivations.hh" -#include "nixexpr-ast.hh" #include "globals.hh" +#include <cstring> + #define LocalNoInline(f) static f __attribute__((noinline)); f #define LocalNoInlineNoReturn(f) static f __attribute__((noinline, noreturn)); f @@ -15,23 +16,134 @@ namespace nix { -EvalState::EvalState() - : normalForms(32768), primOps(128) +std::ostream & operator << (std::ostream & str, Value & v) { - nrEvaluated = nrCached = 0; + switch (v.type) { + case tInt: + str << v.integer; + break; + case tBool: + str << (v.boolean ? "true" : "false"); + break; + case tString: + str << "\""; + for (const char * i = v.string.s; *i; i++) + if (*i == '\"' || *i == '\\') str << "\\" << *i; + else if (*i == '\n') str << "\\n"; + else if (*i == '\r') str << "\\r"; + else if (*i == '\t') str << "\\t"; + else str << *i; + str << "\""; + break; + case tPath: + str << v.path; // !!! escaping? + break; + case tNull: + str << "true"; + break; + case tAttrs: + str << "{ "; + foreach (Bindings::iterator, i, *v.attrs) + str << (string) i->first << " = " << i->second.value << "; "; + str << "}"; + break; + case tList: + str << "[ "; + for (unsigned int n = 0; n < v.list.length; ++n) + str << *v.list.elems[n] << " "; + str << "]"; + break; + case tThunk: + case tCopy: + str << "<CODE>"; + break; + case tLambda: + str << "<LAMBDA>"; + break; + case tPrimOp: + str << "<PRIMOP>"; + break; + case tPrimOpApp: + str << "<PRIMOP-APP>"; + break; + default: + throw Error("invalid value"); + } + return str; +} - initNixExprHelpers(); - addPrimOps(); +string showType(const Value & v) +{ + switch (v.type) { + case tInt: return "an integer"; + case tBool: return "a boolean"; + case tString: return "a string"; + case tPath: return "a path"; + case tNull: return "null"; + case tAttrs: return "an attribute set"; + case tList: return "a list"; + case tThunk: return "a thunk"; + case tApp: return "a function application"; + case tLambda: return "a function"; + case tCopy: return "a copy"; + case tBlackhole: return "a black hole"; + case tPrimOp: return "a built-in function"; + case tPrimOpApp: return "a partially applied built-in function"; + } + abort(); +} + +EvalState::EvalState() + : sWith(symbols.create("<with>")) + , sOutPath(symbols.create("outPath")) + , sDrvPath(symbols.create("drvPath")) + , sType(symbols.create("type")) + , sMeta(symbols.create("meta")) + , sName(symbols.create("name")) + , sSystem(symbols.create("system")) + , baseEnv(allocEnv(128)) + , baseEnvDispl(0) + , staticBaseEnv(false, 0) +{ + nrEnvs = nrValuesInEnvs = nrValues = nrListElems = 0; + nrEvaluated = recursionDepth = maxRecursionDepth = 0; + deepestStack = (char *) -1; + + createBaseEnv(); + allowUnsafeEquality = getEnv("NIX_NO_UNSAFE_EQ", "") == ""; } +EvalState::~EvalState() +{ + assert(recursionDepth == 0); +} + + +void EvalState::addConstant(const string & name, Value & v) +{ + staticBaseEnv.vars[symbols.create(name)] = baseEnvDispl; + baseEnv.values[baseEnvDispl++] = v; + string name2 = string(name, 0, 2) == "__" ? string(name, 2) : name; + (*baseEnv.values[0].attrs)[symbols.create(name2)].value = v; +} + + void EvalState::addPrimOp(const string & name, unsigned int arity, PrimOp primOp) { - primOps.set(toATerm(name), makePrimOpDef(arity, ATmakeBlob(0, (void *) primOp))); + Value v; + string name2 = string(name, 0, 2) == "__" ? string(name, 2) : name; + v.type = tPrimOp; + v.primOp.arity = arity; + v.primOp.fun = primOp; + v.primOp.name = strdup(name2.c_str()); + staticBaseEnv.vars[symbols.create(name)] = baseEnvDispl; + baseEnv.values[baseEnvDispl++] = v; + (*baseEnv.values[0].attrs)[symbols.create(name2)].value = v; } @@ -50,6 +162,11 @@ LocalNoInlineNoReturn(void throwEvalError(const char * s, const string & s2)) throw EvalError(format(s) % s2); } +LocalNoInlineNoReturn(void throwEvalError(const char * s, const string & s2, const string & s3)) +{ + throw EvalError(format(s) % s2 % s3); +} + LocalNoInlineNoReturn(void throwTypeError(const char * s)) { throw TypeError(s); @@ -60,9 +177,19 @@ LocalNoInlineNoReturn(void throwTypeError(const char * s, const string & s2)) throw TypeError(format(s) % s2); } -LocalNoInline(void addErrorPrefix(Error & e, const char * s)) +LocalNoInlineNoReturn(void throwTypeError(const char * s, const Pos & pos, const string & s2)) +{ + throw TypeError(format(s) % pos % s2); +} + +LocalNoInlineNoReturn(void throwTypeError(const char * s, const Pos & pos)) { - e.addPrefix(s); + throw TypeError(format(s) % pos); +} + +LocalNoInlineNoReturn(void throwAssertionError(const char * s, const Pos & pos)) +{ + throw AssertionError(format(s) % pos); } LocalNoInline(void addErrorPrefix(Error & e, const char * s, const string & s2)) @@ -70,845 +197,884 @@ LocalNoInline(void addErrorPrefix(Error & e, const char * s, const string & s2)) e.addPrefix(format(s) % s2); } -LocalNoInline(void addErrorPrefix(Error & e, const char * s, const string & s2, const string & s3)) +LocalNoInline(void addErrorPrefix(Error & e, const char * s, const Pos & pos)) +{ + e.addPrefix(format(s) % pos); +} + +LocalNoInline(void addErrorPrefix(Error & e, const char * s, const string & s2, const Pos & pos)) { - e.addPrefix(format(s) % s2 % s3); + e.addPrefix(format(s) % s2 % pos); } -/* Pattern-match `pat' against `arg'. The result is a set of - substitutions (`subs') and a set of recursive substitutions - (`subsRecursive'). The latter can refer to the variables bound by - both `subs' and `subsRecursive'. */ -static void patternMatch(EvalState & state, - Pattern pat, Expr arg, ATermMap & subs, ATermMap & subsRecursive) +void mkString(Value & v, const char * s) { - ATerm name; - ATermList formals; - Pattern pat1, pat2; - ATermBool ellipsis; - - if (matchVarPat(pat, name)) - subs.set(name, arg); + v.type = tString; + v.string.s = strdup(s); + v.string.context = 0; +} - else if (matchAttrsPat(pat, formals, ellipsis)) { - arg = evalExpr(state, arg); +void mkString(Value & v, const string & s, const PathSet & context) +{ + mkString(v, s.c_str()); + if (!context.empty()) { + unsigned int n = 0; + v.string.context = new const char *[context.size() + 1]; + foreach (PathSet::const_iterator, i, context) + v.string.context[n++] = strdup(i->c_str()); + v.string.context[n] = 0; + } +} - /* Get the actual arguments. */ - ATermMap attrs; - queryAllAttrs(arg, attrs); - unsigned int nrAttrs = attrs.size(); - /* For each formal argument, get the actual argument. If - there is no matching actual argument but the formal - argument has a default, use the default. */ - unsigned int attrsUsed = 0; - for (ATermIterator i(formals); i; ++i) { - Expr name, def; - DefaultValue def2; - if (!matchFormal(*i, name, def2)) abort(); /* can't happen */ - - Expr value = attrs[name]; - - if (value == 0) { - if (!matchDefaultValue(def2, def)) def = 0; - if (def == 0) throw TypeError(format("the argument named `%1%' required by the function is missing") - % aterm2String(name)); - subsRecursive.set(name, def); - } else { - attrsUsed++; - attrs.remove(name); - subs.set(name, value); - } +void mkPath(Value & v, const char * s) +{ + v.type = tPath; + v.path = strdup(s); +} + +Value * EvalState::lookupVar(Env * env, const VarRef & var) +{ + for (unsigned int l = var.level; l; --l, env = env->up) ; + + if (var.fromWith) { + while (1) { + Bindings::iterator j = env->values[0].attrs->find(var.name); + if (j != env->values[0].attrs->end()) + return &j->second.value; + if (env->prevWith == 0) + throwEvalError("undefined variable `%1%'", var.name); + for (unsigned int l = env->prevWith; l; --l, env = env->up) ; } + } else + return &env->values[var.displ]; +} - /* Check that each actual argument is listed as a formal - argument (unless the attribute match specifies a `...'). */ - if (ellipsis == eFalse && attrsUsed != nrAttrs) - throw TypeError(format("the function does not expect an argument named `%1%'") - % aterm2String(attrs.begin()->key)); - } - else if (matchAtPat(pat, pat1, pat2)) { - patternMatch(state, pat1, arg, subs, subsRecursive); - patternMatch(state, pat2, arg, subs, subsRecursive); - } +Value * EvalState::allocValues(unsigned int count) +{ + nrValues += count; + return new Value[count]; // !!! check destructor +} - else abort(); + +Env & EvalState::allocEnv(unsigned int size) +{ + nrEnvs++; + nrValuesInEnvs += size; + Env * env = (Env *) malloc(sizeof(Env) + size * sizeof(Value)); + return *env; } -/* Substitute an argument set into the body of a function. */ -static Expr substArgs(EvalState & state, - Expr body, Pattern pat, Expr arg) +void EvalState::mkList(Value & v, unsigned int length) { - ATermMap subs(16), subsRecursive(16); - - patternMatch(state, pat, arg, subs, subsRecursive); - - /* If we used any default values, make a recursive attribute set - out of the (argument-name, value) tuples. This is so that we - can support default values that refer to each other, e.g. ({x, - y ? x + x}: y) {x = "foo";} evaluates to "foofoo". */ - if (subsRecursive.size() != 0) { - ATermList recAttrs = ATempty; - foreach (ATermMap::const_iterator, i, subs) - recAttrs = ATinsert(recAttrs, makeBind(i->key, i->value, makeNoPos())); - foreach (ATermMap::const_iterator, i, subsRecursive) - recAttrs = ATinsert(recAttrs, makeBind(i->key, i->value, makeNoPos())); - Expr rec = makeRec(recAttrs, ATempty); - foreach (ATermMap::const_iterator, i, subsRecursive) - subs.set(i->key, makeSelect(rec, i->key)); - } + v.type = tList; + v.list.length = length; + v.list.elems = new Value *[length]; + nrListElems += length; +} - return substitute(Substitution(0, &subs), body); + +void EvalState::mkAttrs(Value & v) +{ + v.type = tAttrs; + v.attrs = new Bindings; } -/* Transform a mutually recursive set into a non-recursive set. Each - attribute is transformed into an expression that has all references - to attributes substituted with selection expressions on the - original set. E.g., e = `rec {x = f x y; y = x;}' becomes `{x = f - (e.x) (e.y); y = e.x;}'. */ -LocalNoInline(ATerm expandRec(EvalState & state, ATerm e, ATermList rbnds, ATermList nrbnds)) +void EvalState::mkThunk_(Value & v, Expr * expr) { - ATerm name; - Expr e2; - Pos pos; - Expr eOverrides = 0; + mkThunk(v, baseEnv, expr); +} - /* Create the substitution list. */ - ATermMap subs(ATgetLength(rbnds) + ATgetLength(nrbnds)); - for (ATermIterator i(rbnds); i; ++i) { - if (!matchBind(*i, name, e2, pos)) abort(); /* can't happen */ - subs.set(name, makeSelect(e, name)); - } - for (ATermIterator i(nrbnds); i; ++i) { - if (!matchBind(*i, name, e2, pos)) abort(); /* can't happen */ - if (name == sOverrides) eOverrides = e2; - subs.set(name, e2); - } - /* If the rec contains an attribute called `__overrides', then - evaluate it, and add the attributes in that set to the rec. - This allows overriding of recursive attributes, which is - otherwise not possible. (You can use the // operator to - replace an attribute, but other attributes in the rec will - still reference the original value, because that value has been - substituted into the bodies of the other attributes. Hence we - need __overrides.) */ - ATermMap overrides; - if (eOverrides) { - eOverrides = evalExpr(state, eOverrides); - queryAllAttrs(eOverrides, overrides, false); - foreach (ATermMap::const_iterator, i, overrides) - subs.set(i->key, i->value); +void EvalState::cloneAttrs(Value & src, Value & dst) +{ + mkAttrs(dst); + foreach (Bindings::iterator, i, *src.attrs) { + Attr & a = (*dst.attrs)[i->first]; + mkCopy(a.value, i->second.value); + a.pos = i->second.pos; } +} - Substitution subs_(0, &subs); - /* Create the non-recursive set. */ - ATermMap as(ATgetLength(rbnds) + ATgetLength(nrbnds)); - for (ATermIterator i(rbnds); i; ++i) { - if (!matchBind(*i, name, e2, pos)) abort(); /* can't happen */ - as.set(name, makeAttrRHS(substitute(subs_, e2), pos)); - } +void EvalState::evalFile(const Path & path, Value & v) +{ + startNest(nest, lvlTalkative, format("evaluating file `%1%'") % path); - if (eOverrides) - foreach (ATermMap::const_iterator, i, overrides) - as.set(i->key, makeAttrRHS(i->value, makeNoPos())); + Expr * e = parseTrees[path]; - /* Copy the non-recursive bindings. !!! inefficient */ - for (ATermIterator i(nrbnds); i; ++i) { - if (!matchBind(*i, name, e2, pos)) abort(); /* can't happen */ - as.set(name, makeAttrRHS(e2, pos)); + if (!e) { + e = parseExprFromFile(*this, path); + parseTrees[path] = e; + } + + try { + eval(e, v); + } catch (Error & e) { + addErrorPrefix(e, "while evaluating the file `%1%':\n", path); + throw; } - - return makeAttrs(as); } -LocalNoInline(Expr updateAttrs(Expr e1, Expr e2)) +struct RecursionCounter { - /* Note: e1 and e2 should be in normal form. */ + EvalState & state; + RecursionCounter(EvalState & state) : state(state) + { + state.recursionDepth++; + if (state.recursionDepth > state.maxRecursionDepth) + state.maxRecursionDepth = state.recursionDepth; + } + ~RecursionCounter() + { + state.recursionDepth--; + } +}; - ATermMap attrs; - queryAllAttrs(e1, attrs, true); - queryAllAttrs(e2, attrs, true); - return makeAttrs(attrs); -} +void EvalState::eval(Env & env, Expr * e, Value & v) +{ + /* When changing this function, make sure that you don't cause a + (large) increase in stack consumption! */ + /* !!! Disable this eventually. */ + RecursionCounter r(*this); + char x; + if (&x < deepestStack) deepestStack = &x; + + //debug(format("eval: %1%") % *e); -string evalString(EvalState & state, Expr e, PathSet & context) -{ - e = evalExpr(state, e); - string s; - if (!matchStr(e, s, context)) - throwTypeError("value is %1% while a string was expected", showType(e)); - return s; + checkInterrupt(); + + nrEvaluated++; + + e->eval(*this, env, v); } -string evalStringNoCtx(EvalState & state, Expr e) +void EvalState::eval(Expr * e, Value & v) { - PathSet context; - string s = evalString(state, e, context); - if (!context.empty()) - throw EvalError(format("the string `%1%' is not allowed to refer to a store path (such as `%2%')") - % s % *(context.begin())); - return s; + eval(baseEnv, e, v); } -int evalInt(EvalState & state, Expr e) +bool EvalState::evalBool(Env & env, Expr * e) { - e = evalExpr(state, e); - int i; - if (!matchInt(e, i)) - throwTypeError("value is %1% while an integer was expected", showType(e)); - return i; + Value v; + eval(env, e, v); + if (v.type != tBool) + throwTypeError("value is %1% while a Boolean was expected", showType(v)); + return v.boolean; } -bool evalBool(EvalState & state, Expr e) +void EvalState::evalAttrs(Env & env, Expr * e, Value & v) { - e = evalExpr(state, e); - if (e == eTrue) return true; - else if (e == eFalse) return false; - else throwTypeError("value is %1% while a boolean was expected", showType(e)); + eval(env, e, v); + if (v.type != tAttrs) + throwTypeError("value is %1% while an attribute set was expected", showType(v)); } -ATermList evalList(EvalState & state, Expr e) +void Expr::eval(EvalState & state, Env & env, Value & v) { - e = evalExpr(state, e); - ATermList list; - if (!matchList(e, list)) - throwTypeError("value is %1% while a list was expected", showType(e)); - return list; + abort(); } -static void flattenList(EvalState & state, Expr e, ATermList & result) +void ExprInt::eval(EvalState & state, Env & env, Value & v) { - ATermList es; - e = evalExpr(state, e); - if (matchList(e, es)) - for (ATermIterator i(es); i; ++i) - flattenList(state, *i, result); - else - result = ATinsert(result, e); + mkInt(v, n); } -ATermList flattenList(EvalState & state, Expr e) +void ExprString::eval(EvalState & state, Env & env, Value & v) { - ATermList result = ATempty; - flattenList(state, e, result); - return ATreverse(result); + mkString(v, s.c_str()); } -string coerceToString(EvalState & state, Expr e, PathSet & context, - bool coerceMore, bool copyToStore) +void ExprPath::eval(EvalState & state, Env & env, Value & v) { - e = evalExpr(state, e); + mkPath(v, s.c_str()); +} - string s; - if (matchStr(e, s, context)) return s; +void ExprAttrs::eval(EvalState & state, Env & env, Value & v) +{ + state.mkAttrs(v); - ATerm s2; - if (matchPath(e, s2)) { - Path path(canonPath(aterm2String(s2))); + if (recursive) { + /* Create a new environment that contains the attributes in + this `rec'. */ + Env & env2(state.allocEnv(attrs.size() + inherited.size())); + env2.up = &env; - if (!copyToStore) return path; + unsigned int displ = 0; - if (isDerivation(path)) - throw EvalError(format("file names are not allowed to end in `%1%'") - % drvExtension); + /* The recursive attributes are evaluated in the new + environment. */ + foreach (Attrs::iterator, i, attrs) { + nix::Attr & a = (*v.attrs)[i->first]; + mkCopy(a.value, env2.values[displ]); + mkThunk(env2.values[displ++], env2, i->second.first); + a.pos = &i->second.second; + } - Path dstPath; - if (state.srcToStore[path] != "") - dstPath = state.srcToStore[path]; - else { - dstPath = readOnlyMode - ? computeStorePathForPath(path).first - : store->addToStore(path); - state.srcToStore[path] = dstPath; - printMsg(lvlChatty, format("copied source `%1%' -> `%2%'") - % path % dstPath); + /* The inherited attributes, on the other hand, are + evaluated in the original environment. */ + foreach (list<Inherited>::iterator, i, inherited) { + nix::Attr & a = (*v.attrs)[i->first.name]; + Value * v2 = state.lookupVar(&env, i->first); + mkCopy(a.value, *v2); + mkCopy(env2.values[displ++], *v2); + a.pos = &i->second; } - context.insert(dstPath); - return dstPath; - } - - ATermList es; - if (matchAttrs(e, es)) { - Expr e2 = queryAttr(e, "outPath"); - if (!e2) throwTypeError("cannot coerce an attribute set (except a derivation) to a string"); - return coerceToString(state, e2, context, coerceMore, copyToStore); } - if (coerceMore) { - - /* Note that `false' is represented as an empty string for - shell scripting convenience, just like `null'. */ - if (e == eTrue) return "1"; - if (e == eFalse) return ""; - int n; - if (matchInt(e, n)) return int2String(n); - if (matchNull(e)) return ""; + else { + foreach (Attrs::iterator, i, attrs) { + nix::Attr & a = (*v.attrs)[i->first]; + mkThunk(a.value, env, i->second.first); + a.pos = &i->second.second; + } - if (matchList(e, es)) { - string result; - es = flattenList(state, e); - bool first = true; - for (ATermIterator i(es); i; ++i) { - if (!first) result += " "; else first = false; - result += coerceToString(state, *i, - context, coerceMore, copyToStore); - } - return result; + foreach (list<Inherited>::iterator, i, inherited) { + nix::Attr & a = (*v.attrs)[i->first.name]; + mkCopy(a.value, *state.lookupVar(&env, i->first)); + a.pos = &i->second; } } - - throwTypeError("cannot coerce %1% to a string", showType(e)); } -/* Common implementation of `+', ConcatStrings and `~'. */ -static ATerm concatStrings(EvalState & state, ATermVector & args, - string separator = "") +void ExprLet::eval(EvalState & state, Env & env, Value & v) { - if (args.empty()) return makeStr("", PathSet()); - - PathSet context; - std::ostringstream s; + /* Create a new environment that contains the attributes in this + `let'. */ + Env & env2(state.allocEnv(attrs->attrs.size() + attrs->inherited.size())); + env2.up = &env; - /* If the first element is a path, then the result will also be a - path, we don't copy anything (yet - that's done later, since - paths are copied when they are used in a derivation), and none - of the strings are allowed to have contexts. */ - ATerm dummy; - args.front() = evalExpr(state, args.front()); - bool isPath = matchPath(args.front(), dummy); - - for (ATermVector::const_iterator i = args.begin(); i != args.end(); ++i) { - if (i != args.begin()) s << separator; - s << coerceToString(state, *i, context, false, !isPath); - } + unsigned int displ = 0; - if (isPath && !context.empty()) - throw EvalError(format("a string that refers to a store path cannot be appended to a path, in `%1%'") - % s.str()); - - return isPath - ? makePath(toATerm(s.str())) - : makeStr(s.str(), context); + /* The recursive attributes are evaluated in the new + environment. */ + foreach (ExprAttrs::Attrs::iterator, i, attrs->attrs) + mkThunk(env2.values[displ++], env2, i->second.first); + + /* The inherited attributes, on the other hand, are evaluated in + the original environment. */ + foreach (list<ExprAttrs::Inherited>::iterator, i, attrs->inherited) + mkCopy(env2.values[displ++], *state.lookupVar(&env, i->first)); + + state.eval(env2, body, v); } -Path coerceToPath(EvalState & state, Expr e, PathSet & context) +void ExprList::eval(EvalState & state, Env & env, Value & v) { - string path = coerceToString(state, e, context, false, false); - if (path == "" || path[0] != '/') - throw EvalError(format("string `%1%' doesn't represent an absolute path") % path); - return path; + state.mkList(v, elems.size()); + Value * vs = state.allocValues(v.list.length); + for (unsigned int n = 0; n < v.list.length; ++n) { + v.list.elems[n] = &vs[n]; + mkThunk(vs[n], env, elems[n]); + } } -Expr autoCallFunction(Expr e, const ATermMap & args) +void ExprVar::eval(EvalState & state, Env & env, Value & v) { - Pattern pat; - ATerm body, pos; - ATermList formals; - ATermBool ellipsis; - - /* !!! this should be more general */ - if (matchFunction(e, pat, body, pos) && matchAttrsPat(pat, formals, ellipsis)) { - ATermMap actualArgs(ATgetLength(formals)); - - for (ATermIterator i(formals); i; ++i) { - Expr name, def, value; ATerm def2; - if (!matchFormal(*i, name, def2)) abort(); - if ((value = args.get(name))) - actualArgs.set(name, makeAttrRHS(value, makeNoPos())); - else if (!matchDefaultValue(def2, def)) - throw TypeError(format("cannot auto-call a function that has an argument without a default value (`%1%')") - % aterm2String(name)); - } - - e = makeCall(e, makeAttrs(actualArgs)); + Value * v2 = state.lookupVar(&env, info); + state.forceValue(*v2); + v = *v2; +} + + +void ExprSelect::eval(EvalState & state, Env & env, Value & v) +{ + Value v2; + state.evalAttrs(env, e, v2); + Bindings::iterator i = v2.attrs->find(name); + if (i == v2.attrs->end()) + throwEvalError("attribute `%1%' missing", name); + try { + state.forceValue(i->second.value); + } catch (Error & e) { + addErrorPrefix(e, "while evaluating the attribute `%1%' at %2%:\n", + name, *i->second.pos); + throw; } - - return e; + v = i->second.value; } -/* Evaluation of various language constructs. These have been taken - out of evalExpr2 to reduce stack space usage. (GCC is really dumb - about stack space: it just adds up all the local variables and - temporaries of every scope into one huge stack frame. This is - really bad for deeply recursive functions.) */ +void ExprOpHasAttr::eval(EvalState & state, Env & env, Value & v) +{ + Value vAttrs; + state.evalAttrs(env, e, vAttrs); + mkBool(v, vAttrs.attrs->find(name) != vAttrs.attrs->end()); +} -LocalNoInline(Expr evalVar(EvalState & state, ATerm name)) +void ExprLambda::eval(EvalState & state, Env & env, Value & v) { - ATerm primOp = state.primOps.get(name); - if (!primOp) - throw EvalError(format("impossible: undefined variable `%1%'") % aterm2String(name)); - int arity; - ATermBlob fun; - if (!matchPrimOpDef(primOp, arity, fun)) abort(); - if (arity == 0) - /* !!! backtrace for primop call */ - return ((PrimOp) ATgetBlobData(fun)) (state, ATermVector()); - else - return makePrimOp(arity, fun, ATempty); + v.type = tLambda; + v.lambda.env = &env; + v.lambda.fun = this; } -LocalNoInline(Expr evalCall(EvalState & state, Expr fun, Expr arg)) +void ExprApp::eval(EvalState & state, Env & env, Value & v) { - Pattern pat; - ATerm pos; - Expr body; - - /* Evaluate the left-hand side. */ - fun = evalExpr(state, fun); - - /* Is it a primop or a function? */ - int arity; - ATermBlob funBlob; - ATermList args; - if (matchPrimOp(fun, arity, funBlob, args)) { - args = ATinsert(args, arg); - if (ATgetLength(args) == arity) { - /* Put the arguments in a vector in reverse (i.e., - actual) order. */ - ATermVector args2(arity); - for (ATermIterator i(args); i; ++i) - args2[--arity] = *i; - /* !!! backtrace for primop call */ - return ((PrimOp) ATgetBlobData(funBlob)) - (state, args2); - } else - /* Need more arguments, so propagate the primop. */ - return makePrimOp(arity, funBlob, args); - } + Value vFun; + state.eval(env, e1, vFun); + Value vArg; + mkThunk(vArg, env, e2); // !!! should this be on the heap? + state.callFunction(vFun, vArg, v); +} - else if (matchFunction(fun, pat, body, pos)) { - try { - return evalExpr(state, substArgs(state, body, pat, arg)); - } catch (Error & e) { - addErrorPrefix(e, "while evaluating the function at %1%:\n", - showPos(pos)); - throw; + +void EvalState::callFunction(Value & fun, Value & arg, Value & v) +{ + if (fun.type == tPrimOp || fun.type == tPrimOpApp) { + unsigned int argsLeft = + fun.type == tPrimOp ? fun.primOp.arity : fun.primOpApp.argsLeft; + if (argsLeft == 1) { + /* We have all the arguments, so call the primop. First + find the primop. */ + Value * primOp = &fun; + while (primOp->type == tPrimOpApp) primOp = primOp->primOpApp.left; + assert(primOp->type == tPrimOp); + unsigned int arity = primOp->primOp.arity; + + /* Put all the arguments in an array. */ + Value * vArgs[arity]; + unsigned int n = arity - 1; + vArgs[n--] = &arg; + for (Value * arg = &fun; arg->type == tPrimOpApp; arg = arg->primOpApp.left) + vArgs[n--] = arg->primOpApp.right; + + /* And call the primop. */ + try { + primOp->primOp.fun(*this, vArgs, v); + } catch (Error & e) { + addErrorPrefix(e, "while evaluating the builtin function `%1%':\n", primOp->primOp.name); + throw; + } + } else { + Value * v2 = allocValues(2); + v2[0] = fun; + v2[1] = arg; + v.type = tPrimOpApp; + v.primOpApp.left = &v2[0]; + v.primOpApp.right = &v2[1]; + v.primOpApp.argsLeft = argsLeft - 1; } + return; } + + if (fun.type != tLambda) + throwTypeError("attempt to call something which is neither a function nor a primop (built-in operation) but %1%", + showType(fun)); + + unsigned int size = + (fun.lambda.fun->arg.empty() ? 0 : 1) + + (fun.lambda.fun->matchAttrs ? fun.lambda.fun->formals->formals.size() : 0); + Env & env2(allocEnv(size)); + env2.up = fun.lambda.env; + + unsigned int displ = 0; + + if (!fun.lambda.fun->matchAttrs) + env2.values[displ++] = arg; + + else { + forceAttrs(arg); - else throwTypeError( - "attempt to call something which is neither a function nor a primop (built-in operation) but %1%", - showType(fun)); -} + if (!fun.lambda.fun->arg.empty()) + env2.values[displ++] = arg; + /* For each formal argument, get the actual argument. If + there is no matching actual argument but the formal + argument has a default, use the default. */ + unsigned int attrsUsed = 0; + foreach (Formals::Formals_::iterator, i, fun.lambda.fun->formals->formals) { + Bindings::iterator j = arg.attrs->find(i->name); + if (j == arg.attrs->end()) { + if (!i->def) throwTypeError("function at %1% called without required argument `%2%'", + fun.lambda.fun->pos, i->name); + mkThunk(env2.values[displ++], env2, i->def); + } else { + attrsUsed++; + mkCopy(env2.values[displ++], j->second.value); + } + } + + /* Check that each actual argument is listed as a formal + argument (unless the attribute match specifies a `...'). + TODO: show the names of the expected/unexpected + arguments. */ + if (!fun.lambda.fun->formals->ellipsis && attrsUsed != arg.attrs->size()) + throwTypeError("function at %1% called with unexpected argument", fun.lambda.fun->pos); + } -LocalNoInline(Expr evalSelect(EvalState & state, Expr e, ATerm name)) -{ - ATerm pos; - string s = aterm2String(name); - Expr a = queryAttr(evalExpr(state, e), s, pos); - if (!a) throwEvalError("attribute `%1%' missing", s); try { - return evalExpr(state, a); + eval(env2, fun.lambda.fun->body, v); } catch (Error & e) { - addErrorPrefix(e, "while evaluating the attribute `%1%' at %2%:\n", - s, showPos(pos)); + addErrorPrefix(e, "while evaluating the function at %1%:\n", fun.lambda.fun->pos); throw; } } -LocalNoInline(Expr evalAssert(EvalState & state, Expr cond, Expr body, ATerm pos)) +void EvalState::autoCallFunction(const Bindings & args, Value & fun, Value & res) { - if (!evalBool(state, cond)) - throw AssertionError(format("assertion failed at %1%") % showPos(pos)); - return evalExpr(state, body); -} + forceValue(fun); + if (fun.type != tLambda || !fun.lambda.fun->matchAttrs) { + res = fun; + return; + } -LocalNoInline(Expr evalWith(EvalState & state, Expr defs, Expr body, ATerm pos)) -{ - ATermMap attrs; - try { - defs = evalExpr(state, defs); - queryAllAttrs(defs, attrs); - } catch (Error & e) { - addErrorPrefix(e, "while evaluating the `with' definitions at %1%:\n", - showPos(pos)); - throw; + Value actualArgs; + mkAttrs(actualArgs); + + foreach (Formals::Formals_::iterator, i, fun.lambda.fun->formals->formals) { + Bindings::const_iterator j = args.find(i->name); + if (j != args.end()) + (*actualArgs.attrs)[i->name] = j->second; + else if (!i->def) + throwTypeError("cannot auto-call a function that has an argument without a default value (`%1%')", i->name); } - try { - body = substitute(Substitution(0, &attrs), body); - checkVarDefs(state.primOps, body); - return evalExpr(state, body); - } catch (Error & e) { - addErrorPrefix(e, "while evaluating the `with' body at %1%:\n", - showPos(pos)); - throw; - } + + callFunction(fun, actualArgs, res); } -LocalNoInline(Expr evalHasAttr(EvalState & state, Expr e, ATerm name)) +void ExprWith::eval(EvalState & state, Env & env, Value & v) { - ATermMap attrs; - queryAllAttrs(evalExpr(state, e), attrs); - return makeBool(attrs.get(name) != 0); + Env & env2(state.allocEnv(1)); + env2.up = &env; + env2.prevWith = prevWith; + + state.evalAttrs(env, attrs, env2.values[0]); + + state.eval(env2, body, v); } -LocalNoInline(Expr evalPlusConcat(EvalState & state, Expr e)) +void ExprIf::eval(EvalState & state, Env & env, Value & v) { - Expr e1, e2; - ATermList es; + state.eval(env, state.evalBool(env, cond) ? then : else_, v); +} + - ATermVector args; +void ExprAssert::eval(EvalState & state, Env & env, Value & v) +{ + if (!state.evalBool(env, cond)) + throwAssertionError("assertion failed at %1%", pos); + state.eval(env, body, v); +} + - if (matchOpPlus(e, e1, e2)) { - - /* !!! Awful compatibility hack for `drv + /path'. - According to regular concatenation, /path should be - copied to the store and its store path should be - appended to the string. However, in Nix <= 0.10, /path - was concatenated. So handle that case separately, but - do print out a warning. This code can go in Nix 0.12, - maybe. */ - e1 = evalExpr(state, e1); - e2 = evalExpr(state, e2); - - ATermList as; - ATerm p; - if (matchAttrs(e1, as) && matchPath(e2, p)) { - static bool haveWarned = false; - warnOnce(haveWarned, format( - "concatenation of a derivation and a path is deprecated; " - "you should write `drv + \"%1%\"' instead of `drv + %1%'") - % aterm2String(p)); - PathSet context; - return makeStr( - coerceToString(state, makeSelect(e1, toATerm("outPath")), context) - + aterm2String(p), context); - } +void ExprOpNot::eval(EvalState & state, Env & env, Value & v) +{ + mkBool(v, !state.evalBool(env, e)); +} - args.push_back(e1); - args.push_back(e2); - } - else if (matchConcatStrings(e, es)) - for (ATermIterator i(es); i; ++i) args.push_back(*i); - - try { - return concatStrings(state, args); - } catch (Error & e) { - addErrorPrefix(e, "in a string concatenation:\n"); - throw; - } +void ExprOpEq::eval(EvalState & state, Env & env, Value & v) +{ + Value v1; state.eval(env, e1, v1); + Value v2; state.eval(env, e2, v2); + mkBool(v, state.eqValues(v1, v2)); } -LocalNoInline(Expr evalSubPath(EvalState & state, Expr e1, Expr e2)) +void ExprOpNEq::eval(EvalState & state, Env & env, Value & v) { - static bool haveWarned = false; - warnOnce(haveWarned, "the subpath operator (~) is deprecated, use string concatenation (+) instead"); - ATermVector args; - args.push_back(e1); - args.push_back(e2); - return concatStrings(state, args, "/"); + Value v1; state.eval(env, e1, v1); + Value v2; state.eval(env, e2, v2); + mkBool(v, !state.eqValues(v1, v2)); } -LocalNoInline(Expr evalOpConcat(EvalState & state, Expr e1, Expr e2)) +void ExprOpAnd::eval(EvalState & state, Env & env, Value & v) { - try { - ATermList l1 = evalList(state, e1); - ATermList l2 = evalList(state, e2); - return makeList(ATconcat(l1, l2)); - } catch (Error & e) { - addErrorPrefix(e, "in a list concatenation:\n"); - throw; - } + mkBool(v, state.evalBool(env, e1) && state.evalBool(env, e2)); } -/* Implementation of the `==' and `!=' operators. */ -LocalNoInline(bool areEqual(EvalState & state, Expr e1, Expr e2)) +void ExprOpOr::eval(EvalState & state, Env & env, Value & v) { - e1 = evalExpr(state, e1); - e2 = evalExpr(state, e2); - - /* We cannot test functions/primops for equality, and we currently - don't support testing equality between attribute sets or lists - - that would have to be a deep equality test to be sound. */ - AFun sym1 = ATgetAFun(e1); - AFun sym2 = ATgetAFun(e2); + mkBool(v, state.evalBool(env, e1) || state.evalBool(env, e2)); +} - if (sym1 != sym2) return false; - /* Functions are incomparable. */ - if (sym1 == symFunction || sym1 == symPrimOp) return false; +void ExprOpImpl::eval(EvalState & state, Env & env, Value & v) +{ + mkBool(v, !state.evalBool(env, e1) || state.evalBool(env, e2)); +} - if (!state.allowUnsafeEquality && sym1 == symAttrs) - throw EvalError("comparison of attribute sets is not implemented"); - /* !!! This allows comparisons of infinite data structures to - succeed, such as `let x = [x]; in x == x'. This is - undesirable, since equivalent (?) terms such as `let x = [x]; y - = [y]; in x == y' don't terminate. */ - if (e1 == e2) return true; +void ExprOpUpdate::eval(EvalState & state, Env & env, Value & v) +{ + Value v2; + state.evalAttrs(env, e1, v2); + + state.cloneAttrs(v2, v); + + state.evalAttrs(env, e2, v2); - if (sym1 == symList) { - ATermList es1; matchList(e1, es1); - ATermList es2; matchList(e2, es2); - if (ATgetLength(es1) != ATgetLength(es2)) return false; - ATermIterator i(es1), j(es2); - while (*i) { - if (!areEqual(state, *i, *j)) return false; - ++i; ++j; + foreach (Bindings::iterator, i, *v2.attrs) { + Attr & a = (*v.attrs)[i->first]; + mkCopy(a.value, i->second.value); + a.pos = i->second.pos; + } +} + + +void ExprOpConcatLists::eval(EvalState & state, Env & env, Value & v) +{ + Value v1; state.eval(env, e1, v1); + state.forceList(v1); + Value v2; state.eval(env, e2, v2); + state.forceList(v2); + state.mkList(v, v1.list.length + v2.list.length); + for (unsigned int n = 0; n < v1.list.length; ++n) + v.list.elems[n] = v1.list.elems[n]; + for (unsigned int n = 0; n < v2.list.length; ++n) + v.list.elems[n + v1.list.length] = v2.list.elems[n]; +} + + +void ExprConcatStrings::eval(EvalState & state, Env & env, Value & v) +{ + PathSet context; + std::ostringstream s; + + bool first = true, isPath = false; + Value vStr; + + foreach (vector<Expr *>::iterator, i, *es) { + state.eval(env, *i, vStr); + + /* If the first element is a path, then the result will also + be a path, we don't copy anything (yet - that's done later, + since paths are copied when they are used in a derivation), + and none of the strings are allowed to have contexts. */ + if (first) { + isPath = vStr.type == tPath; + first = false; } - return true; + + s << state.coerceToString(vStr, context, false, !isPath); } - - return false; + + if (isPath && !context.empty()) + throwEvalError("a string that refers to a store path cannot be appended to a path, in `%1%'", s.str()); + + if (isPath) + mkPath(v, s.str().c_str()); + else + mkString(v, s.str(), context); } -static char * deepestStack = (char *) -1; /* for measuring stack usage */ +void EvalState::forceValue(Value & v) +{ + if (v.type == tThunk) { + ValueType saved = v.type; + try { + v.type = tBlackhole; + eval(*v.thunk.env, v.thunk.expr, v); + } catch (Error & e) { + v.type = saved; + throw; + } + } + else if (v.type == tCopy) { + forceValue(*v.val); + v = *v.val; + } + else if (v.type == tApp) + callFunction(*v.app.left, *v.app.right, v); + else if (v.type == tBlackhole) + throwEvalError("infinite recursion encountered"); +} -Expr evalExpr2(EvalState & state, Expr e) +void EvalState::strictForceValue(Value & v) { - /* When changing this function, make sure that you don't cause a - (large) increase in stack consumption! */ + forceValue(v); - char x; - if (&x < deepestStack) deepestStack = &x; - - Expr e1, e2, e3; - ATerm name, pos; - AFun sym = ATgetAFun(e); - - /* Normal forms. */ - if (sym == symStr || - sym == symPath || - sym == symNull || - sym == symInt || - sym == symBool || - sym == symFunction || - sym == symAttrs || - sym == symList || - sym == symPrimOp) - return e; + if (v.type == tAttrs) { + foreach (Bindings::iterator, i, *v.attrs) + strictForceValue(i->second.value); + } - /* The `Closed' constructor is just a way to prevent substitutions - into expressions not containing free variables. */ - if (matchClosed(e, e1)) - return evalExpr(state, e1); - - /* Any encountered variables must be primops (since undefined - variables are detected after parsing). */ - if (matchVar(e, name)) return evalVar(state, name); - - /* Function application. */ - if (matchCall(e, e1, e2)) return evalCall(state, e1, e2); - - /* Attribute selection. */ - if (matchSelect(e, e1, name)) return evalSelect(state, e1, name); - - /* Mutually recursive sets. */ - ATermList rbnds, nrbnds; - if (matchRec(e, rbnds, nrbnds)) - return expandRec(state, e, rbnds, nrbnds); - - /* Conditionals. */ - if (matchIf(e, e1, e2, e3)) - return evalExpr(state, evalBool(state, e1) ? e2 : e3); - - /* Assertions. */ - if (matchAssert(e, e1, e2, pos)) return evalAssert(state, e1, e2, pos); - - /* Withs. */ - if (matchWith(e, e1, e2, pos)) return evalWith(state, e1, e2, pos); - - /* Generic equality/inequality. Note that the behaviour on - composite data (lists, attribute sets) and functions is - undefined, since the subterms of those terms are not evaluated. - However, we don't want to make (==) strict, because that would - make operations like `big_derivation == null' very slow (unless - we were to evaluate them side-by-side). */ - if (matchOpEq(e, e1, e2)) return makeBool(areEqual(state, e1, e2)); - - if (matchOpNEq(e, e1, e2)) return makeBool(!areEqual(state, e1, e2)); - - /* Negation. */ - if (matchOpNot(e, e1)) - return makeBool(!evalBool(state, e1)); + else if (v.type == tList) { + for (unsigned int n = 0; n < v.list.length; ++n) + strictForceValue(*v.list.elems[n]); + } +} - /* Implication. */ - if (matchOpImpl(e, e1, e2)) - return makeBool(!evalBool(state, e1) || evalBool(state, e2)); - /* Conjunction (logical AND). */ - if (matchOpAnd(e, e1, e2)) - return makeBool(evalBool(state, e1) && evalBool(state, e2)); +int EvalState::forceInt(Value & v) +{ + forceValue(v); + if (v.type != tInt) + throwTypeError("value is %1% while an integer was expected", showType(v)); + return v.integer; +} + - /* Disjunction (logical OR). */ - if (matchOpOr(e, e1, e2)) - return makeBool(evalBool(state, e1) || evalBool(state, e2)); +bool EvalState::forceBool(Value & v) +{ + forceValue(v); + if (v.type != tBool) + throwTypeError("value is %1% while a Boolean was expected", showType(v)); + return v.boolean; +} - /* Attribute set update (//). */ - if (matchOpUpdate(e, e1, e2)) - return updateAttrs(evalExpr(state, e1), evalExpr(state, e2)); - /* Attribute existence test (?). */ - if (matchOpHasAttr(e, e1, name)) return evalHasAttr(state, e1, name); +void EvalState::forceAttrs(Value & v) +{ + forceValue(v); + if (v.type != tAttrs) + throwTypeError("value is %1% while an attribute set was expected", showType(v)); +} - /* String or path concatenation. */ - if (sym == symOpPlus || sym == symConcatStrings) - return evalPlusConcat(state, e); - /* Backwards compatability: subpath operator (~). */ - if (matchSubPath(e, e1, e2)) return evalSubPath(state, e1, e2); +void EvalState::forceList(Value & v) +{ + forceValue(v); + if (v.type != tList) + throwTypeError("value is %1% while a list was expected", showType(v)); +} - /* List concatenation. */ - if (matchOpConcat(e, e1, e2)) return evalOpConcat(state, e1, e2); - /* Barf. */ - abort(); +void EvalState::forceFunction(Value & v) +{ + forceValue(v); + if (v.type != tLambda && v.type != tPrimOp && v.type != tPrimOpApp) + throwTypeError("value is %1% while a function was expected", showType(v)); } -Expr evalExpr(EvalState & state, Expr e) +string EvalState::forceString(Value & v) { - checkInterrupt(); + forceValue(v); + if (v.type != tString) + throwTypeError("value is %1% while a string was expected", showType(v)); + return string(v.string.s); +} -#if 0 - startNest(nest, lvlVomit, - format("evaluating expression: %1%") % e); -#endif - - state.nrEvaluated++; - - /* Consult the memo table to quickly get the normal form of - previously evaluated expressions. */ - Expr nf = state.normalForms.get(e); - if (nf) { - if (nf == makeBlackHole()) - throwEvalError("infinite recursion encountered"); - state.nrCached++; - return nf; - } - /* Otherwise, evaluate and memoize. */ - state.normalForms.set(e, makeBlackHole()); - try { - nf = evalExpr2(state, e); - } catch (Error & err) { - state.normalForms.remove(e); - throw; - } - state.normalForms.set(e, nf); - return nf; +string EvalState::forceString(Value & v, PathSet & context) +{ + string s = forceString(v); + if (v.string.context) + for (const char * * p = v.string.context; *p; ++p) + context.insert(*p); + return s; } -Expr evalFile(EvalState & state, const Path & path) +string EvalState::forceStringNoCtx(Value & v) { - startNest(nest, lvlTalkative, format("evaluating file `%1%'") % path); - Expr e = parseExprFromFile(state, path); - try { - return evalExpr(state, e); - } catch (Error & e) { - e.addPrefix(format("while evaluating the file `%1%':\n") - % path); - throw; - } + string s = forceString(v); + if (v.string.context) + throwEvalError("the string `%1%' is not allowed to refer to a store path (such as `%2%')", + v.string.s, v.string.context[0]); + return s; } -static Expr strictEvalExpr(EvalState & state, Expr e, ATermMap & nfs); +bool EvalState::isDerivation(Value & v) +{ + if (v.type != tAttrs) return false; + Bindings::iterator i = v.attrs->find(sType); + return i != v.attrs->end() && forceStringNoCtx(i->second.value) == "derivation"; +} -static Expr strictEvalExpr_(EvalState & state, Expr e, ATermMap & nfs) +string EvalState::coerceToString(Value & v, PathSet & context, + bool coerceMore, bool copyToStore) { - e = evalExpr(state, e); + forceValue(v); - ATermList as; - if (matchAttrs(e, as)) { - ATermList as2 = ATempty; - for (ATermIterator i(as); i; ++i) { - ATerm name; Expr e; ATerm pos; - if (!matchBind(*i, name, e, pos)) abort(); /* can't happen */ - as2 = ATinsert(as2, makeBind(name, strictEvalExpr(state, e, nfs), pos)); - } - return makeAttrs(ATreverse(as2)); + string s; + + if (v.type == tString) { + if (v.string.context) + for (const char * * p = v.string.context; *p; ++p) + context.insert(*p); + return v.string.s; } - - ATermList es; - if (matchList(e, es)) { - ATermList es2 = ATempty; - for (ATermIterator i(es); i; ++i) - es2 = ATinsert(es2, strictEvalExpr(state, *i, nfs)); - return makeList(ATreverse(es2)); + + if (v.type == tPath) { + Path path(canonPath(v.path)); + + if (!copyToStore) return path; + + if (nix::isDerivation(path)) + throwEvalError("file names are not allowed to end in `%1%'", drvExtension); + + Path dstPath; + if (srcToStore[path] != "") + dstPath = srcToStore[path]; + else { + dstPath = readOnlyMode + ? computeStorePathForPath(path).first + : store->addToStore(path); + srcToStore[path] = dstPath; + printMsg(lvlChatty, format("copied source `%1%' -> `%2%'") + % path % dstPath); + } + + context.insert(dstPath); + return dstPath; } - - return e; -} + if (v.type == tAttrs) { + Bindings::iterator i = v.attrs->find(sOutPath); + if (i == v.attrs->end()) + throwTypeError("cannot coerce an attribute set (except a derivation) to a string"); + return coerceToString(i->second.value, context, coerceMore, copyToStore); + } -static Expr strictEvalExpr(EvalState & state, Expr e, ATermMap & nfs) -{ - Expr nf = nfs.get(e); - if (nf) return nf; + if (coerceMore) { - nf = strictEvalExpr_(state, e, nfs); + /* Note that `false' is represented as an empty string for + shell scripting convenience, just like `null'. */ + if (v.type == tBool && v.boolean) return "1"; + if (v.type == tBool && !v.boolean) return ""; + if (v.type == tInt) return int2String(v.integer); + if (v.type == tNull) return ""; - nfs.set(e, nf); + if (v.type == tList) { + string result; + for (unsigned int n = 0; n < v.list.length; ++n) { + result += coerceToString(*v.list.elems[n], + context, coerceMore, copyToStore); + if (n < v.list.length - 1 + /* !!! not quite correct */ + && (v.list.elems[n]->type != tList || v.list.elems[n]->list.length != 0)) + result += " "; + } + return result; + } + } - return nf; + throwTypeError("cannot coerce %1% to a string", showType(v)); } -Expr strictEvalExpr(EvalState & state, Expr e) +Path EvalState::coerceToPath(Value & v, PathSet & context) { - ATermMap strictNormalForms; - return strictEvalExpr(state, e, strictNormalForms); + string path = coerceToString(v, context, false, false); + if (path == "" || path[0] != '/') + throwEvalError("string `%1%' doesn't represent an absolute path", path); + return path; } -/* Yes, this is a really bad idea... */ -extern "C" { - unsigned long AT_calcAllocatedSize(); +bool EvalState::eqValues(Value & v1, Value & v2) +{ + forceValue(v1); + forceValue(v2); + + /* !!! Hack to support some old broken code that relies on pointer + equality tests between attribute sets. (Specifically, + builderDefs calls uniqList on a list of attribute sets.) Will + remove this eventually. */ + if (&v1 == &v2) return true; + + if (v1.type != v2.type) return false; + + switch (v1.type) { + + case tInt: + return v1.integer == v2.integer; + + case tBool: + return v1.boolean == v2.boolean; + + case tString: { + /* Compare both the string and its context. */ + if (strcmp(v1.string.s, v2.string.s) != 0) return false; + const char * * p = v1.string.context, * * q = v2.string.context; + if (!p && !q) return true; + if (!p || !q) return false; + for ( ; *p && *q; ++p, ++q) + if (strcmp(*p, *q) != 0) return false; + if (*p || *q) return false; + return true; + } + + case tPath: + return strcmp(v1.path, v2.path) == 0; + + case tNull: + return true; + + case tList: + if (v1.list.length != v2.list.length) return false; + for (unsigned int n = 0; n < v1.list.length; ++n) + if (!eqValues(*v1.list.elems[n], *v2.list.elems[n])) return false; + return true; + + case tAttrs: { + if (v1.attrs->size() != v2.attrs->size()) return false; + Bindings::iterator i, j; + for (i = v1.attrs->begin(), j = v2.attrs->begin(); i != v1.attrs->end(); ++i, ++j) + if (i->first != j->first || !eqValues(i->second.value, j->second.value)) + return false; + return true; + } + + /* Functions are incomparable. */ + case tLambda: + case tPrimOp: + case tPrimOpApp: + return false; + + default: + throwEvalError("cannot compare %1% with %2%", showType(v1), showType(v2)); + } } -void printEvalStats(EvalState & state) + +void EvalState::printStats() { char x; bool showStats = getEnv("NIX_SHOW_STATS", "0") != "0"; - printMsg(showStats ? lvlInfo : lvlDebug, - format("evaluated %1% expressions, %2% cache hits, %3%%% efficiency, used %4% ATerm bytes, used %5% bytes of stack space") - % state.nrEvaluated % state.nrCached - % ((float) state.nrCached / (float) state.nrEvaluated * 100) - % AT_calcAllocatedSize() - % (&x - deepestStack)); - if (showStats) - printATermMapStats(); + Verbosity v = showStats ? lvlInfo : lvlDebug; + printMsg(v, "evaluation statistics:"); + printMsg(v, format(" expressions evaluated: %1%") % nrEvaluated); + printMsg(v, format(" stack space used: %1% bytes") % (&x - deepestStack)); + printMsg(v, format(" max eval() nesting depth: %1%") % maxRecursionDepth); + printMsg(v, format(" stack space per eval() level: %1% bytes") + % ((&x - deepestStack) / (float) maxRecursionDepth)); + printMsg(v, format(" environments allocated: %1% (%2% bytes)") + % nrEnvs % (nrEnvs * sizeof(Env))); + printMsg(v, format(" values allocated in environments: %1% (%2% bytes)") + % nrValuesInEnvs % (nrValuesInEnvs * sizeof(Value))); + printMsg(v, format(" list elements: %1% (%2% bytes)") + % nrListElems % (nrListElems * sizeof(Value *))); + printMsg(v, format(" misc. values allocated: %1% (%2% bytes)") + % nrValues % (nrValues * sizeof(Value))); + printMsg(v, format(" symbols in symbol table: %1%") % symbols.size()); } - + } diff --git a/src/libexpr/eval.hh b/src/libexpr/eval.hh index fed6d34726..1a9862c295 100644 --- a/src/libexpr/eval.hh +++ b/src/libexpr/eval.hh @@ -3,17 +3,165 @@ #include <map> -#include "aterm.hh" #include "nixexpr.hh" +#include "symbol-table.hh" namespace nix { class Hash; - +class EvalState; +struct Env; +struct Value; +struct Attr; + +typedef std::map<Symbol, Attr> Bindings; + + +typedef enum { + tInt = 1, + tBool, + tString, + tPath, + tNull, + tAttrs, + tList, + tThunk, + tApp, + tLambda, + tCopy, + tBlackhole, + tPrimOp, + tPrimOpApp, +} ValueType; + + +typedef void (* PrimOp) (EvalState & state, Value * * args, Value & v); + + +struct Value +{ + ValueType type; + union + { + int integer; + bool boolean; + + /* Strings in the evaluator carry a so-called `context' (the + ATermList) which is a list of strings representing store + paths. This is to allow users to write things like + + "--with-freetype2-library=" + freetype + "/lib" + + where `freetype' is a derivation (or a source to be copied + to the store). If we just concatenated the strings without + keeping track of the referenced store paths, then if the + string is used as a derivation attribute, the derivation + will not have the correct dependencies in its inputDrvs and + inputSrcs. + + The semantics of the context is as follows: when a string + with context C is used as a derivation attribute, then the + derivations in C will be added to the inputDrvs of the + derivation, and the other store paths in C will be added to + the inputSrcs of the derivations. + + For canonicity, the store paths should be in sorted order. */ + struct { + const char * s; + const char * * context; // must be in sorted order + } string; + + const char * path; + Bindings * attrs; + struct { + unsigned int length; + Value * * elems; + } list; + struct { + Env * env; + Expr * expr; + } thunk; + struct { + Value * left, * right; + } app; + struct { + Env * env; + ExprLambda * fun; + } lambda; + Value * val; + struct { + PrimOp fun; + char * name; + unsigned int arity; + } primOp; + struct { + Value * left, * right; + unsigned int argsLeft; + } primOpApp; + }; +}; + + +struct Env +{ + Env * up; + unsigned int prevWith; // nr of levels up to next `with' environment + Value values[0]; +}; + + +struct Attr +{ + Value value; + Pos * pos; + Attr() : pos(&noPos) { }; +}; + + +static inline void mkInt(Value & v, int n) +{ + v.type = tInt; + v.integer = n; +} + + +static inline void mkBool(Value & v, bool b) +{ + v.type = tBool; + v.boolean = b; +} + + +static inline void mkThunk(Value & v, Env & env, Expr * expr) +{ + v.type = tThunk; + v.thunk.env = &env; + v.thunk.expr = expr; +} + + +static inline void mkCopy(Value & v, Value & src) +{ + v.type = tCopy; + v.val = &src; +} + + +static inline void mkApp(Value & v, Value & left, Value & right) +{ + v.type = tApp; + v.app.left = &left; + v.app.right = &right; +} + + +void mkString(Value & v, const char * s); +void mkString(Value & v, const string & s, const PathSet & context = PathSet()); +void mkPath(Value & v, const char * s); + -typedef std::map<Path, PathSet> DrvRoots; typedef std::map<Path, Hash> DrvHashes; /* Cache for calls to addToStore(); maps source paths to the store @@ -22,75 +170,153 @@ typedef std::map<Path, Path> SrcToStore; struct EvalState; -/* Note: using a ATermVector is safe here, since when we call a primop - we also have an ATermList on the stack. */ -typedef Expr (* PrimOp) (EvalState &, const ATermVector & args); + +std::ostream & operator << (std::ostream & str, Value & v); -struct EvalState +class EvalState { - ATermMap normalForms; - ATermMap primOps; - DrvRoots drvRoots; +public: DrvHashes drvHashes; /* normalised derivation hashes */ - SrcToStore srcToStore; - unsigned int nrEvaluated; - unsigned int nrCached; + SymbolTable symbols; + + const Symbol sWith, sOutPath, sDrvPath, sType, sMeta, sName, sSystem; + +private: + SrcToStore srcToStore; bool allowUnsafeEquality; + std::map<Path, Expr *> parseTrees; + +public: + EvalState(); + ~EvalState(); + + /* Evaluate an expression read from the given file to normal + form. */ + void evalFile(const Path & path, Value & v); + + /* Evaluate an expression to normal form, storing the result in + value `v'. */ + void eval(Expr * e, Value & v); + void eval(Env & env, Expr * e, Value & v); + + /* Evaluation the expression, then verify that it has the expected + type. */ + bool evalBool(Env & env, Expr * e); + void evalAttrs(Env & env, Expr * e, Value & v); + + /* If `v' is a thunk, enter it and overwrite `v' with the result + of the evaluation of the thunk. If `v' is a delayed function + application, call the function and overwrite `v' with the + result. Otherwise, this is a no-op. */ + void forceValue(Value & v); + + /* Force a value, then recursively force list elements and + attributes. */ + void strictForceValue(Value & v); + + /* Force `v', and then verify that it has the expected type. */ + int forceInt(Value & v); + bool forceBool(Value & v); + void forceAttrs(Value & v); + void forceList(Value & v); + void forceFunction(Value & v); // either lambda or primop + string forceString(Value & v); + string forceString(Value & v, PathSet & context); + string forceStringNoCtx(Value & v); + + /* Return true iff the value `v' denotes a derivation (i.e. a + set with attribute `type = "derivation"'). */ + bool isDerivation(Value & v); + + /* String coercion. Converts strings, paths and derivations to a + string. If `coerceMore' is set, also converts nulls, integers, + booleans and lists to a string. If `copyToStore' is set, + referenced paths are copied to the Nix store as a side effect.q */ + string coerceToString(Value & v, PathSet & context, + bool coerceMore = false, bool copyToStore = true); + + /* Path coercion. Converts strings, paths and derivations to a + path. The result is guaranteed to be a canonicalised, absolute + path. Nothing is copied to the store. */ + Path coerceToPath(Value & v, PathSet & context); + +private: + + /* The base environment, containing the builtin functions and + values. */ + Env & baseEnv; + + unsigned int baseEnvDispl; + +public: + + /* The same, but used during parsing to resolve variables. */ + StaticEnv staticBaseEnv; // !!! should be private + +private: + + void createBaseEnv(); + + void addConstant(const string & name, Value & v); - void addPrimOps(); void addPrimOp(const string & name, unsigned int arity, PrimOp primOp); -}; + Value * lookupVar(Env * env, const VarRef & var); + + friend class ExprVar; + friend class ExprAttrs; + friend class ExprLet; -/* Evaluate an expression to normal form. */ -Expr evalExpr(EvalState & state, Expr e); +public: + + /* Do a deep equality test between two values. That is, list + elements and attributes are compared recursively. */ + bool eqValues(Value & v1, Value & v2); -/* Evaluate an expression read from the given file to normal form. */ -Expr evalFile(EvalState & state, const Path & path); + void callFunction(Value & fun, Value & arg, Value & v); -/* Evaluate an expression, and recursively evaluate list elements and - attributes. If `canonicalise' is true, we remove things like - position information and make sure that attribute sets are in - sorded order. */ -Expr strictEvalExpr(EvalState & state, Expr e); + /* Automatically call a function for which each argument has a + default value or has a binding in the `args' map. */ + void autoCallFunction(const Bindings & args, Value & fun, Value & res); + + /* Allocation primitives. */ + Value * allocValues(unsigned int count); + Env & allocEnv(unsigned int size); -/* Specific results. */ -string evalString(EvalState & state, Expr e, PathSet & context); -string evalStringNoCtx(EvalState & state, Expr e); -int evalInt(EvalState & state, Expr e); -bool evalBool(EvalState & state, Expr e); -ATermList evalList(EvalState & state, Expr e); + void mkList(Value & v, unsigned int length); + void mkAttrs(Value & v); + void mkThunk_(Value & v, Expr * expr); + + void cloneAttrs(Value & src, Value & dst); -/* Flatten nested lists into a single list (or expand a singleton into - a list). */ -ATermList flattenList(EvalState & state, Expr e); + /* Print statistics. */ + void printStats(); -/* String coercion. Converts strings, paths and derivations to a - string. If `coerceMore' is set, also converts nulls, integers, - booleans and lists to a string. */ -string coerceToString(EvalState & state, Expr e, PathSet & context, - bool coerceMore = false, bool copyToStore = true); +private: + + unsigned long nrEnvs; + unsigned long nrValuesInEnvs; + unsigned long nrValues; + unsigned long nrListElems; + unsigned long nrEvaluated; + unsigned int recursionDepth; + unsigned int maxRecursionDepth; + char * deepestStack; /* for measuring stack usage */ + + friend class RecursionCounter; +}; -/* Path coercion. Converts strings, paths and derivations to a path. - The result is guaranteed to be an canonicalised, absolute path. - Nothing is copied to the store. */ -Path coerceToPath(EvalState & state, Expr e, PathSet & context); -/* Automatically call a function for which each argument has a default - value or has a binding in the `args' map. Note: result is a call, - not a normal form; it should be evaluated by calling evalExpr(). */ -Expr autoCallFunction(Expr e, const ATermMap & args); +/* Return a string representing the type of the value `v'. */ +string showType(const Value & v); -/* Print statistics. */ -void printEvalStats(EvalState & state); - } diff --git a/src/libexpr/expr-to-xml.cc b/src/libexpr/expr-to-xml.cc deleted file mode 100644 index 1e59eebfc4..0000000000 --- a/src/libexpr/expr-to-xml.cc +++ /dev/null @@ -1,186 +0,0 @@ -#include "expr-to-xml.hh" -#include "xml-writer.hh" -#include "nixexpr-ast.hh" -#include "aterm.hh" -#include "util.hh" - -#include <cstdlib> - - -namespace nix { - - -static XMLAttrs singletonAttrs(const string & name, const string & value) -{ - XMLAttrs attrs; - attrs[name] = value; - return attrs; -} - - -/* set<Expr> is safe because all the expressions are also reachable - from the stack, therefore can't be garbage-collected. */ -typedef set<Expr> ExprSet; - - -static void printTermAsXML(Expr e, XMLWriter & doc, PathSet & context, - ExprSet & drvsSeen, bool location); - - -static void showAttrs(const ATermMap & attrs, XMLWriter & doc, - PathSet & context, ExprSet & drvsSeen, bool location) -{ - StringSet names; - for (ATermMap::const_iterator i = attrs.begin(); i != attrs.end(); ++i) - names.insert(aterm2String(i->key)); - for (StringSet::iterator i = names.begin(); i != names.end(); ++i) { - ATerm attrRHS = attrs.get(toATerm(*i)); - ATerm attr; - Pos pos; - XMLAttrs xmlAttrs; - - xmlAttrs["name"] = *i; - if(matchAttrRHS(attrRHS, attr, pos)) { - ATerm path; - int line, column; - if (location && matchPos(pos, path, line, column)) { - xmlAttrs["path"] = aterm2String(path); - xmlAttrs["line"] = (format("%1%") % line).str(); - xmlAttrs["column"] = (format("%1%") % column).str(); - } - } else - abort(); // Should not happen. - - XMLOpenElement _(doc, "attr", xmlAttrs); - printTermAsXML(attr, doc, context, drvsSeen, location); - } -} - - -static void printPatternAsXML(Pattern pat, XMLWriter & doc) -{ - ATerm name; - ATermList formals; - Pattern pat1, pat2; - ATermBool ellipsis; - if (matchVarPat(pat, name)) - doc.writeEmptyElement("varpat", singletonAttrs("name", aterm2String(name))); - else if (matchAttrsPat(pat, formals, ellipsis)) { - XMLOpenElement _(doc, "attrspat"); - for (ATermIterator i(formals); i; ++i) { - Expr name; ATerm dummy; - if (!matchFormal(*i, name, dummy)) abort(); - doc.writeEmptyElement("attr", singletonAttrs("name", aterm2String(name))); - } - if (ellipsis == eTrue) doc.writeEmptyElement("ellipsis"); - } - else if (matchAtPat(pat, pat1, pat2)) { - XMLOpenElement _(doc, "at"); - printPatternAsXML(pat1, doc); - printPatternAsXML(pat2, doc); - } -} - - -static void printTermAsXML(Expr e, XMLWriter & doc, PathSet & context, - ExprSet & drvsSeen, bool location) -{ - XMLAttrs attrs; - string s; - ATerm s2; - int i; - ATermList as, es; - ATerm pat, body, pos; - - checkInterrupt(); - - if (matchStr(e, s, context)) /* !!! show the context? */ - doc.writeEmptyElement("string", singletonAttrs("value", s)); - - else if (matchPath(e, s2)) - doc.writeEmptyElement("path", singletonAttrs("value", aterm2String(s2))); - - else if (matchNull(e)) - doc.writeEmptyElement("null"); - - else if (matchInt(e, i)) - doc.writeEmptyElement("int", singletonAttrs("value", (format("%1%") % i).str())); - - else if (e == eTrue) - doc.writeEmptyElement("bool", singletonAttrs("value", "true")); - - else if (e == eFalse) - doc.writeEmptyElement("bool", singletonAttrs("value", "false")); - - else if (matchAttrs(e, as)) { - ATermMap attrs; - queryAllAttrs(e, attrs, true); - - Expr aRHS = attrs.get(toATerm("type")); - Expr a = NULL; - if (aRHS) - matchAttrRHS(aRHS, a, pos); - if (a && matchStr(a, s, context) && s == "derivation") { - - XMLAttrs xmlAttrs; - Path outPath, drvPath; - - aRHS = attrs.get(toATerm("drvPath")); - matchAttrRHS(aRHS, a, pos); - if (matchStr(a, drvPath, context)) - xmlAttrs["drvPath"] = drvPath; - - aRHS = attrs.get(toATerm("outPath")); - matchAttrRHS(aRHS, a, pos); - if (matchStr(a, outPath, context)) - xmlAttrs["outPath"] = outPath; - - XMLOpenElement _(doc, "derivation", xmlAttrs); - - if (drvsSeen.find(e) == drvsSeen.end()) { - drvsSeen.insert(e); - showAttrs(attrs, doc, context, drvsSeen, location); - } else - doc.writeEmptyElement("repeated"); - } - - else { - XMLOpenElement _(doc, "attrs"); - showAttrs(attrs, doc, context, drvsSeen, location); - } - } - - else if (matchList(e, es)) { - XMLOpenElement _(doc, "list"); - for (ATermIterator i(es); i; ++i) - printTermAsXML(*i, doc, context, drvsSeen, location); - } - - else if (matchFunction(e, pat, body, pos)) { - ATerm path; - int line, column; - XMLAttrs xmlAttrs; - if (location && matchPos(pos, path, line, column)) { - xmlAttrs["path"] = aterm2String(path); - xmlAttrs["line"] = (format("%1%") % line).str(); - xmlAttrs["column"] = (format("%1%") % column).str(); - } - XMLOpenElement _(doc, "function", xmlAttrs); - printPatternAsXML(pat, doc); - } - - else - doc.writeEmptyElement("unevaluated"); -} - - -void printTermAsXML(Expr e, std::ostream & out, PathSet & context, bool location) -{ - XMLWriter doc(true, out); - XMLOpenElement root(doc, "expr"); - ExprSet drvsSeen; - printTermAsXML(e, doc, context, drvsSeen, location); -} - - -} diff --git a/src/libexpr/expr-to-xml.hh b/src/libexpr/expr-to-xml.hh deleted file mode 100644 index de9d55f320..0000000000 --- a/src/libexpr/expr-to-xml.hh +++ /dev/null @@ -1,16 +0,0 @@ -#ifndef __EXPR_TO_XML_H -#define __EXPR_TO_XML_H - -#include <string> -#include <map> - -#include "nixexpr.hh" -#include "aterm.hh" - -namespace nix { - -void printTermAsXML(Expr e, std::ostream & out, PathSet & context, bool location = false); - -} - -#endif /* !__EXPR_TO_XML_H */ diff --git a/src/libexpr/get-drvs.cc b/src/libexpr/get-drvs.cc index 1442d7988b..82a92416be 100644 --- a/src/libexpr/get-drvs.cc +++ b/src/libexpr/get-drvs.cc @@ -1,5 +1,4 @@ #include "get-drvs.hh" -#include "nixexpr-ast.hh" #include "util.hh" @@ -8,17 +7,10 @@ namespace nix { string DrvInfo::queryDrvPath(EvalState & state) const { - if (drvPath == "") { - Expr a = attrs->get(toATerm("drvPath")); - - /* Backwards compatibility hack with user environments made by - Nix <= 0.10: these contain illegal Path("") expressions. */ - ATerm t; - if (a && matchPath(evalExpr(state, a), t)) - return aterm2String(t); - + if (drvPath == "" && attrs) { + Bindings::iterator i = attrs->find(state.sDrvPath); PathSet context; - (string &) drvPath = a ? coerceToPath(state, a, context) : ""; + (string &) drvPath = i != attrs->end() ? state.coerceToPath(i->second.value, context) : ""; } return drvPath; } @@ -26,11 +18,10 @@ string DrvInfo::queryDrvPath(EvalState & state) const string DrvInfo::queryOutPath(EvalState & state) const { - if (outPath == "") { - Expr a = attrs->get(toATerm("outPath")); - if (!a) throw TypeError("output path missing"); + if (outPath == "" && attrs) { + Bindings::iterator i = attrs->find(state.sOutPath); PathSet context; - (string &) outPath = coerceToPath(state, a, context); + (string &) outPath = i != attrs->end() ? state.coerceToPath(i->second.value, context) : ""; } return outPath; } @@ -38,35 +29,30 @@ string DrvInfo::queryOutPath(EvalState & state) const MetaInfo DrvInfo::queryMetaInfo(EvalState & state) const { - MetaInfo meta; + if (metaInfoRead) return meta; - Expr a = attrs->get(toATerm("meta")); - if (!a) return meta; /* fine, empty meta information */ + (bool &) metaInfoRead = true; + + Bindings::iterator a = attrs->find(state.sMeta); + if (a == attrs->end()) return meta; /* fine, empty meta information */ - ATermMap attrs2; - queryAllAttrs(evalExpr(state, a), attrs2); + state.forceAttrs(a->second.value); - for (ATermMap::const_iterator i = attrs2.begin(); i != attrs2.end(); ++i) { - Expr e = evalExpr(state, i->value); - string s; - PathSet context; + foreach (Bindings::iterator, i, *a->second.value.attrs) { MetaValue value; - int n; - ATermList es; - if (matchStr(e, s, context)) { + state.forceValue(i->second.value); + if (i->second.value.type == tString) { value.type = MetaValue::tpString; - value.stringValue = s; - meta[aterm2String(i->key)] = value; - } else if (matchInt(e, n)) { + value.stringValue = i->second.value.string.s; + } else if (i->second.value.type == tInt) { value.type = MetaValue::tpInt; - value.intValue = n; - meta[aterm2String(i->key)] = value; - } else if (matchList(e, es)) { + value.intValue = i->second.value.integer; + } else if (i->second.value.type == tList) { value.type = MetaValue::tpStrings; - for (ATermIterator j(es); j; ++j) - value.stringValues.push_back(evalStringNoCtx(state, *j)); - meta[aterm2String(i->key)] = value; - } + for (unsigned int j = 0; j < i->second.value.list.length; ++j) + value.stringValues.push_back(state.forceStringNoCtx(*i->second.value.list.elems[j])); + } else continue; + ((MetaInfo &) meta)[i->first] = value; } return meta; @@ -82,73 +68,46 @@ MetaValue DrvInfo::queryMetaInfo(EvalState & state, const string & name) const void DrvInfo::setMetaInfo(const MetaInfo & meta) { - ATermMap metaAttrs; - foreach (MetaInfo::const_iterator, i, meta) { - Expr e; - switch (i->second.type) { - case MetaValue::tpInt: e = makeInt(i->second.intValue); break; - case MetaValue::tpString: e = makeStr(i->second.stringValue); break; - case MetaValue::tpStrings: { - ATermList es = ATempty; - foreach (Strings::const_iterator, j, i->second.stringValues) - es = ATinsert(es, makeStr(*j)); - e = makeList(ATreverse(es)); - break; - } - default: abort(); - } - metaAttrs.set(toATerm(i->first), makeAttrRHS(e, makeNoPos())); - } - attrs->set(toATerm("meta"), makeAttrs(metaAttrs)); + metaInfoRead = true; + this->meta = meta; } -/* Cache for already evaluated derivations. Usually putting ATerms in - a STL container is unsafe (they're not scanning for GC roots), but - here it doesn't matter; everything in this set is reachable from - the stack as well. */ -typedef set<Expr> Exprs; +/* Cache for already considered attrsets. */ +typedef set<Bindings *> Done; -/* Evaluate expression `e'. If it evaluates to an attribute set of - type `derivation', then put information about it in `drvs' (unless - it's already in `doneExprs'). The result boolean indicates whether - it makes sense for the caller to recursively search for derivations - in `e'. */ -static bool getDerivation(EvalState & state, Expr e, - const string & attrPath, DrvInfos & drvs, Exprs & doneExprs) +/* Evaluate value `v'. If it evaluates to an attribute set of type + `derivation', then put information about it in `drvs' (unless it's + already in `doneExprs'). The result boolean indicates whether it + makes sense for the caller to recursively search for derivations in + `v'. */ +static bool getDerivation(EvalState & state, Value & v, + const string & attrPath, DrvInfos & drvs, Done & done) { try { - - ATermList es; - e = evalExpr(state, e); - if (!matchAttrs(e, es)) return true; - - boost::shared_ptr<ATermMap> attrs(new ATermMap()); - queryAllAttrs(e, *attrs, false); - - Expr a = attrs->get(toATerm("type")); - if (!a || evalStringNoCtx(state, a) != "derivation") return true; + state.forceValue(v); + if (!state.isDerivation(v)) return true; /* Remove spurious duplicates (e.g., an attribute set like `rec { x = derivation {...}; y = x;}'. */ - if (doneExprs.find(e) != doneExprs.end()) return false; - doneExprs.insert(e); + if (done.find(v.attrs) != done.end()) return false; + done.insert(v.attrs); DrvInfo drv; - a = attrs->get(toATerm("name")); + Bindings::iterator i = v.attrs->find(state.sName); /* !!! We really would like to have a decent back trace here. */ - if (!a) throw TypeError("derivation name missing"); - drv.name = evalStringNoCtx(state, a); + if (i == v.attrs->end()) throw TypeError("derivation name missing"); + drv.name = state.forceStringNoCtx(i->second.value); - a = attrs->get(toATerm("system")); - if (!a) + i = v.attrs->find(state.sSystem); + if (i == v.attrs->end()) drv.system = "unknown"; else - drv.system = evalStringNoCtx(state, a); + drv.system = state.forceStringNoCtx(i->second.value); - drv.attrs = attrs; + drv.attrs = v.attrs; drv.attrPath = attrPath; @@ -161,11 +120,11 @@ static bool getDerivation(EvalState & state, Expr e, } -bool getDerivation(EvalState & state, Expr e, DrvInfo & drv) +bool getDerivation(EvalState & state, Value & v, DrvInfo & drv) { - Exprs doneExprs; + Done done; DrvInfos drvs; - getDerivation(state, e, "", drvs, doneExprs); + getDerivation(state, v, "", drvs, done); if (drvs.size() != 1) return false; drv = drvs.front(); return true; @@ -178,83 +137,73 @@ static string addToPath(const string & s1, const string & s2) } -static void getDerivations(EvalState & state, Expr e, - const string & pathPrefix, const ATermMap & autoArgs, - DrvInfos & drvs, Exprs & doneExprs) +static void getDerivations(EvalState & state, Value & vIn, + const string & pathPrefix, const Bindings & autoArgs, + DrvInfos & drvs, Done & done) { - e = evalExpr(state, autoCallFunction(evalExpr(state, e), autoArgs)); - + Value v; + state.autoCallFunction(autoArgs, vIn, v); + /* Process the expression. */ - ATermList es; DrvInfo drv; - if (!getDerivation(state, e, pathPrefix, drvs, doneExprs)) - return; + if (!getDerivation(state, v, pathPrefix, drvs, done)) ; - if (matchAttrs(e, es)) { - ATermMap drvMap(ATgetLength(es)); - queryAllAttrs(e, drvMap); + else if (v.type == tAttrs) { /* !!! undocumented hackery to support combining channels in nix-env.cc. */ - bool combineChannels = drvMap.get(toATerm("_combineChannels")); + bool combineChannels = v.attrs->find(state.symbols.create("_combineChannels")) != v.attrs->end(); /* Consider the attributes in sorted order to get more deterministic behaviour in nix-env operations (e.g. when there are names clashes between derivations, the derivation bound to the attribute with the "lower" name should take precedence). */ - typedef std::map<string, Expr> AttrsSorted; - AttrsSorted attrsSorted; - foreach (ATermMap::const_iterator, i, drvMap) - attrsSorted[aterm2String(i->key)] = i->value; + typedef std::map<string, Symbol> SortedSymbols; + SortedSymbols attrs; + foreach (Bindings::iterator, i, *v.attrs) + attrs.insert(std::pair<string, Symbol>(i->first, i->first)); - foreach (AttrsSorted::iterator, i, attrsSorted) { + foreach (SortedSymbols::iterator, i, attrs) { startNest(nest, lvlDebug, format("evaluating attribute `%1%'") % i->first); string pathPrefix2 = addToPath(pathPrefix, i->first); + Value & v2((*v.attrs)[i->second].value); if (combineChannels) - getDerivations(state, i->second, pathPrefix2, autoArgs, drvs, doneExprs); - else if (getDerivation(state, i->second, pathPrefix2, drvs, doneExprs)) { + getDerivations(state, v2, pathPrefix2, autoArgs, drvs, done); + else if (getDerivation(state, v2, pathPrefix2, drvs, done)) { /* If the value of this attribute is itself an attribute set, should we recurse into it? => Only if it has a `recurseForDerivations = true' attribute. */ - ATermList es; - Expr e = evalExpr(state, i->second), e2; - if (matchAttrs(e, es)) { - ATermMap attrs(ATgetLength(es)); - queryAllAttrs(e, attrs, false); - if (((e2 = attrs.get(toATerm("recurseForDerivations"))) - && evalBool(state, e2))) - getDerivations(state, e, pathPrefix2, autoArgs, drvs, doneExprs); + if (v2.type == tAttrs) { + Bindings::iterator j = v2.attrs->find(state.symbols.create("recurseForDerivations")); + if (j != v2.attrs->end() && state.forceBool(j->second.value)) + getDerivations(state, v2, pathPrefix2, autoArgs, drvs, done); } } } - - return; } - if (matchList(e, es)) { - int n = 0; - for (ATermIterator i(es); i; ++i, ++n) { + else if (v.type == tList) { + for (unsigned int n = 0; n < v.list.length; ++n) { startNest(nest, lvlDebug, format("evaluating list element")); string pathPrefix2 = addToPath(pathPrefix, (format("%1%") % n).str()); - if (getDerivation(state, *i, pathPrefix2, drvs, doneExprs)) - getDerivations(state, *i, pathPrefix2, autoArgs, drvs, doneExprs); + if (getDerivation(state, *v.list.elems[n], pathPrefix2, drvs, done)) + getDerivations(state, *v.list.elems[n], pathPrefix2, autoArgs, drvs, done); } - return; } - throw TypeError("expression does not evaluate to a derivation (or a set or list of those)"); + else throw TypeError("expression does not evaluate to a derivation (or a set or list of those)"); } -void getDerivations(EvalState & state, Expr e, const string & pathPrefix, - const ATermMap & autoArgs, DrvInfos & drvs) +void getDerivations(EvalState & state, Value & v, const string & pathPrefix, + const Bindings & autoArgs, DrvInfos & drvs) { - Exprs doneExprs; - getDerivations(state, e, pathPrefix, autoArgs, drvs, doneExprs); + Done done; + getDerivations(state, v, pathPrefix, autoArgs, drvs, done); } diff --git a/src/libexpr/get-drvs.hh b/src/libexpr/get-drvs.hh index b56f547118..ca7d980027 100644 --- a/src/libexpr/get-drvs.hh +++ b/src/libexpr/get-drvs.hh @@ -29,16 +29,19 @@ struct DrvInfo private: string drvPath; string outPath; + + bool metaInfoRead; + MetaInfo meta; public: string name; string attrPath; /* path towards the derivation */ string system; - /* !!! these should really be hidden, and setMetaInfo() should - make a copy since the ATermMap can be shared between multiple - DrvInfos. */ - boost::shared_ptr<ATermMap> attrs; + /* !!! make this private */ + Bindings * attrs; + + DrvInfo() : metaInfoRead(false), attrs(0) { }; string queryDrvPath(EvalState & state) const; string queryOutPath(EvalState & state) const; @@ -62,13 +65,12 @@ public: typedef list<DrvInfo> DrvInfos; -/* Evaluate expression `e'. If it evaluates to a derivation, store - information about the derivation in `drv' and return true. - Otherwise, return false. */ -bool getDerivation(EvalState & state, Expr e, DrvInfo & drv); +/* If value `v' denotes a derivation, store information about the + derivation in `drv' and return true. Otherwise, return false. */ +bool getDerivation(EvalState & state, Value & v, DrvInfo & drv); -void getDerivations(EvalState & state, Expr e, const string & pathPrefix, - const ATermMap & autoArgs, DrvInfos & drvs); +void getDerivations(EvalState & state, Value & v, const string & pathPrefix, + const Bindings & autoArgs, DrvInfos & drvs); } diff --git a/src/libexpr/lexer.l b/src/libexpr/lexer.l index 81aec99e15..f29f9b6843 100644 --- a/src/libexpr/lexer.l +++ b/src/libexpr/lexer.l @@ -8,9 +8,7 @@ %{ -#include "aterm.hh" #include "nixexpr.hh" -#include "nixexpr-ast.hh" #define BISON_HEADER_HACK #include "parser-tab.hh" @@ -21,13 +19,16 @@ namespace nix { static void initLoc(YYLTYPE * loc) { - loc->first_line = 1; - loc->first_column = 1; + loc->first_line = loc->last_line = 1; + loc->first_column = loc->last_column = 1; } static void adjustLoc(YYLTYPE * loc, const char * s, size_t len) { + loc->first_line = loc->last_line; + loc->first_column = loc->last_column; + while (len--) { switch (*s++) { case '\r': @@ -35,17 +36,17 @@ static void adjustLoc(YYLTYPE * loc, const char * s, size_t len) s++; /* fall through */ case '\n': - ++loc->first_line; - loc->first_column = 1; + ++loc->last_line; + loc->last_column = 1; break; default: - ++loc->first_column; + ++loc->last_column; } } } -static Expr unescapeStr(const char * s) +static Expr * unescapeStr(const char * s) { string t; char c; @@ -65,7 +66,7 @@ static Expr unescapeStr(const char * s) } else t += c; } - return makeStr(toATerm(t), ATempty); + return new ExprString(t); } @@ -105,19 +106,20 @@ inherit { return INHERIT; } \/\/ { return UPDATE; } \+\+ { return CONCAT; } -{ID} { yylval->t = toATerm(yytext); return ID; /* !!! alloc */ } +{ID} { yylval->id = strdup(yytext); return ID; } {INT} { int n = atoi(yytext); /* !!! overflow */ - yylval->t = ATmake("<int>", n); + yylval->n = n; return INT; } \" { BEGIN(STRING); return '"'; } <STRING>([^\$\"\\]|\$[^\{\"]|\\.)+ { -/* !!! Not quite right: we want a follow restriction on "$", it - shouldn't be followed by a "{". Right now "$\"" will be consumed - as part of a string, rather than a "$" followed by the string - terminator. Disallow "$\"" for now. */ - yylval->t = unescapeStr(yytext); /* !!! alloc */ + /* !!! Not quite right: we want a follow restriction on + "$", it shouldn't be followed by a "{". Right now + "$\"" will be consumed as part of a string, rather + than a "$" followed by the string terminator. + Disallow "$\"" for now. */ + yylval->e = unescapeStr(yytext); return STR; } <STRING>\$\{ { BEGIN(INITIAL); return DOLLAR_CURLY; } @@ -126,31 +128,31 @@ inherit { return INHERIT; } \'\'(\ *\n)? { BEGIN(IND_STRING); return IND_STRING_OPEN; } <IND_STRING>([^\$\']|\$[^\{\']|\'[^\'\$])+ { - yylval->t = makeIndStr(toATerm(yytext)); + yylval->e = new ExprIndStr(yytext); return IND_STR; } <IND_STRING>\'\'\$ { - yylval->t = makeIndStr(toATerm("$")); + yylval->e = new ExprIndStr("$"); return IND_STR; } <IND_STRING>\'\'\' { - yylval->t = makeIndStr(toATerm("''")); + yylval->e = new ExprIndStr("''"); return IND_STR; } <IND_STRING>\'\'\\. { - yylval->t = unescapeStr(yytext + 2); + yylval->e = unescapeStr(yytext + 2); return IND_STR; } <IND_STRING>\$\{ { BEGIN(INITIAL); return DOLLAR_CURLY; } <IND_STRING>\'\' { BEGIN(INITIAL); return IND_STRING_CLOSE; } <IND_STRING>\' { - yylval->t = makeIndStr(toATerm("'")); + yylval->e = new ExprIndStr("'"); return IND_STR; } <IND_STRING>. return yytext[0]; /* just in case: shouldn't be reached */ -{PATH} { yylval->t = toATerm(yytext); return PATH; /* !!! alloc */ } -{URI} { yylval->t = toATerm(yytext); return URI; /* !!! alloc */ } +{PATH} { yylval->path = strdup(yytext); return PATH; } +{URI} { yylval->uri = strdup(yytext); return URI; } [ \t\r\n]+ /* eat up whitespace */ \#[^\r\n]* /* single-line comments */ diff --git a/src/libexpr/nixexpr-ast.def b/src/libexpr/nixexpr-ast.def deleted file mode 100644 index 00b5f5a137..0000000000 --- a/src/libexpr/nixexpr-ast.def +++ /dev/null @@ -1,97 +0,0 @@ -init initNixExprHelpers - -Pos | string int int | Pos | -NoPos | | Pos | - -Function | Pattern Expr Pos | Expr | -Assert | Expr Expr Pos | Expr | -With | Expr Expr Pos | Expr | -If | Expr Expr Expr | Expr | -OpNot | Expr | Expr | -OpEq | Expr Expr | Expr | -OpNEq | Expr Expr | Expr | -OpAnd | Expr Expr | Expr | -OpOr | Expr Expr | Expr | -OpImpl | Expr Expr | Expr | -OpUpdate | Expr Expr | Expr | -SubPath | Expr Expr | Expr | -OpHasAttr | Expr string | Expr | -OpPlus | Expr Expr | Expr | -OpConcat | Expr Expr | Expr | -ConcatStrings | ATermList | Expr | -Call | Expr Expr | Expr | -Select | Expr string | Expr | -Var | string | Expr | -Int | int | Expr | - -# Strings in the evaluator carry a so-called `context' (the ATermList) -# which is a list of strings representing store paths. This is to -# allow users to write things like -# -# "--with-freetype2-library=" + freetype + "/lib" -# -# where `freetype' is a derivation (or a source to be copied to the -# store). If we just concatenated the strings without keeping track -# of the referenced store paths, then if the string is used as a -# derivation attribute, the derivation will not have the correct -# dependencies in its inputDrvs and inputSrcs. -# -# The semantics of the context is as follows: when a string with -# context C is used as a derivation attribute, then the derivations in -# C will be added to the inputDrvs of the derivation, and the other -# store paths in C will be added to the inputSrcs of the derivations. -# -# For canonicity, the store paths should be in sorted order. -Str | string ATermList | Expr | -Str | string | Expr | ObsoleteStr - -# Internal to the parser, doesn't occur in ASTs. -IndStr | string | Expr | - -# A path is a reference to a file system object that is to be copied -# to the Nix store when used as a derivation attribute. When it is -# concatenated to a string (i.e., `str + path'), it is also copied and -# the resulting store path is concatenated to the string (with the -# store path in the context). If a string or path is concatenated to -# a path (i.e., `path + str' or `path + path'), the result is a new -# path (if the right-hand side is a string, the context must be -# empty). -Path | string | Expr | - -List | ATermList | Expr | -BlackHole | | Expr | -Undefined | | Expr | -Removed | | Expr | -PrimOp | int ATermBlob ATermList | Expr | -Attrs | ATermList | Expr | -Closed | Expr | Expr | -Rec | ATermList ATermList | Expr | -Bool | ATermBool | Expr | -Null | | Expr | - -Bind | string Expr Pos | ATerm | -BindAttrPath | ATermList Expr Pos | ATerm | # desugared during parsing -Bind | string Expr | ATerm | ObsoleteBind -Inherit | Expr ATermList Pos | ATerm | - -Scope | | Expr | - -VarPat | string | Pattern | -AttrsPat | ATermList ATermBool | Pattern | # bool = `...' -AtPat | Pattern Pattern | Pattern | - -Formal | string DefaultValue | ATerm | - -DefaultValue | Expr | DefaultValue | -NoDefaultValue | | DefaultValue | - -True | | ATermBool | -False | | ATermBool | - -PrimOpDef | int ATermBlob | ATerm | - -AttrRHS | Expr Pos | ATerm | - -eTrue = makeBool(makeTrue()) -eFalse = makeBool(makeFalse()) -sOverrides = toATerm("__overrides") diff --git a/src/libexpr/nixexpr.cc b/src/libexpr/nixexpr.cc index 3675dcceaf..898fdb6094 100644 --- a/src/libexpr/nixexpr.cc +++ b/src/libexpr/nixexpr.cc @@ -1,407 +1,325 @@ #include "nixexpr.hh" #include "derivations.hh" #include "util.hh" -#include "aterm.hh" - -#include "nixexpr-ast.hh" -#include "nixexpr-ast.cc" #include <cstdlib> namespace nix { - -string showPos(ATerm pos) + +/* Displaying abstract syntax trees. */ + +std::ostream & operator << (std::ostream & str, Expr & e) { - ATerm path; - int line, column; - if (matchNoPos(pos)) return "undefined position"; - if (!matchPos(pos, path, line, column)) - throw badTerm("position expected", pos); - return (format("`%1%:%2%:%3%'") % aterm2String(path) % line % column).str(); + e.show(str); + return str; } - -ATerm bottomupRewrite(TermFun & f, ATerm e) +void Expr::show(std::ostream & str) { - checkInterrupt(); - - if (ATgetType(e) == AT_APPL) { - AFun fun = ATgetAFun(e); - int arity = ATgetArity(fun); - ATerm args[arity]; - - for (int i = 0; i < arity; ++i) - args[i] = bottomupRewrite(f, ATgetArgument(e, i)); - - e = (ATerm) ATmakeApplArray(fun, args); - } - - else if (ATgetType(e) == AT_LIST) { - ATermList in = (ATermList) e; - ATermList out = ATempty; - - for (ATermIterator i(in); i; ++i) - out = ATinsert(out, bottomupRewrite(f, *i)); - - e = (ATerm) ATreverse(out); - } + abort(); +} - return f(e); +void ExprInt::show(std::ostream & str) +{ + str << n; } +void ExprString::show(std::ostream & str) +{ + str << "\"" << s << "\""; // !!! escaping +} -void queryAllAttrs(Expr e, ATermMap & attrs, bool withPos) +void ExprPath::show(std::ostream & str) { - ATermList bnds; - if (!matchAttrs(e, bnds)) - throw TypeError(format("value is %1% while an attribute set was expected") % showType(e)); + str << s; +} - for (ATermIterator i(bnds); i; ++i) { - ATerm name; - Expr e; - ATerm pos; - if (!matchBind(*i, name, e, pos)) abort(); /* can't happen */ - attrs.set(name, withPos ? makeAttrRHS(e, pos) : e); - } +void ExprVar::show(std::ostream & str) +{ + str << info.name; } +void ExprSelect::show(std::ostream & str) +{ + str << "(" << *e << ")." << name; +} -Expr queryAttr(Expr e, const string & name) +void ExprOpHasAttr::show(std::ostream & str) { - ATerm dummy; - return queryAttr(e, name, dummy); + str << "(" << *e << ") ? " << name; } +void ExprAttrs::show(std::ostream & str) +{ + if (recursive) str << "rec "; + str << "{ "; + foreach (list<Inherited>::iterator, i, inherited) + str << "inherit " << i->first.name << "; "; + foreach (Attrs::iterator, i, attrs) + str << i->first << " = " << *i->second.first << "; "; + str << "}"; +} -Expr queryAttr(Expr e, const string & name, ATerm & pos) +void ExprList::show(std::ostream & str) { - ATermList bnds; - if (!matchAttrs(e, bnds)) - throw TypeError(format("value is %1% while an attribute set was expected") % showType(e)); + str << "[ "; + foreach (vector<Expr *>::iterator, i, elems) + str << "(" << **i << ") "; + str << "]"; +} - for (ATermIterator i(bnds); i; ++i) { - ATerm name2, pos2; - Expr e; - if (!matchBind(*i, name2, e, pos2)) - abort(); /* can't happen */ - if (aterm2String(name2) == name) { - pos = pos2; - return e; +void ExprLambda::show(std::ostream & str) +{ + str << "("; + if (matchAttrs) { + str << "{ "; + bool first = true; + foreach (Formals::Formals_::iterator, i, formals->formals) { + if (first) first = false; else str << ", "; + str << i->name; + if (i->def) str << " ? " << *i->def; } + str << " }"; + if (!arg.empty()) str << " @ "; } - - return 0; + if (!arg.empty()) str << arg; + str << ": " << *body << ")"; } - -Expr makeAttrs(const ATermMap & attrs) +void ExprLet::show(std::ostream & str) { - ATermList bnds = ATempty; - for (ATermMap::const_iterator i = attrs.begin(); i != attrs.end(); ++i) { - Expr e; - ATerm pos; - if (!matchAttrRHS(i->value, e, pos)) - abort(); /* can't happen */ - bnds = ATinsert(bnds, makeBind(i->key, e, pos)); - } - return makeAttrs(bnds); + str << "let "; + foreach (list<ExprAttrs::Inherited>::iterator, i, attrs->inherited) + str << "inherit " << i->first.name << "; "; + foreach (ExprAttrs::Attrs::iterator, i, attrs->attrs) + str << i->first << " = " << *i->second.first << "; "; + str << "in " << *body; } - -static void varsBoundByPattern(ATermMap & map, Pattern pat) +void ExprWith::show(std::ostream & str) { - ATerm name; - ATermList formals; - Pattern pat1, pat2; - ATermBool ellipsis; - /* Use makeRemoved() so that it can be used directly in - substitute(). */ - if (matchVarPat(pat, name)) - map.set(name, makeRemoved()); - else if (matchAttrsPat(pat, formals, ellipsis)) { - for (ATermIterator i(formals); i; ++i) { - ATerm d1; - if (!matchFormal(*i, name, d1)) abort(); - map.set(name, makeRemoved()); - } - } - else if (matchAtPat(pat, pat1, pat2)) { - varsBoundByPattern(map, pat1); - varsBoundByPattern(map, pat2); - } - else abort(); + str << "with " << *attrs << "; " << *body; } +void ExprIf::show(std::ostream & str) +{ + str << "if " << *cond << " then " << *then << " else " << *else_; +} -Expr substitute(const Substitution & subs, Expr e) +void ExprAssert::show(std::ostream & str) { - checkInterrupt(); + str << "assert " << *cond << "; " << *body; +} - //if (subs.size() == 0) return e; +void ExprOpNot::show(std::ostream & str) +{ + str << "! " << *e; +} - ATerm name, pos, e2; +void ExprConcatStrings::show(std::ostream & str) +{ + bool first = true; + foreach (vector<Expr *>::iterator, i, *es) { + if (first) first = false; else str << " + "; + str << **i; + } +} - /* As an optimisation, don't substitute in subterms known to be - closed. */ - if (matchClosed(e, e2)) return e; - if (matchVar(e, name)) { - Expr sub = subs.lookup(name); - if (sub == makeRemoved()) sub = 0; - Expr wrapped; - /* Add a "closed" wrapper around terms that aren't already - closed. The check is necessary to prevent repeated - wrapping, e.g., closed(closed(closed(...))), which kills - caching. */ - return sub ? (matchClosed(sub, wrapped) ? sub : makeClosed(sub)) : e; - } +std::ostream & operator << (std::ostream & str, const Pos & pos) +{ + if (!pos.line) + str << "undefined position"; + else + str << (format("`%1%:%2%:%3%'") % pos.file % pos.line % pos.column).str(); + return str; +} - /* In case of a function, filter out all variables bound by this - function. */ - Pattern pat; - ATerm body; - if (matchFunction(e, pat, body, pos)) { - ATermMap map(16); - varsBoundByPattern(map, pat); - Substitution subs2(&subs, &map); - return makeFunction( - (Pattern) substitute(subs2, (Expr) pat), - substitute(subs2, body), pos); - } - /* Idem for a mutually recursive attribute set. */ - ATermList rbnds, nrbnds; - if (matchRec(e, rbnds, nrbnds)) { - ATermMap map(ATgetLength(rbnds) + ATgetLength(nrbnds)); - for (ATermIterator i(rbnds); i; ++i) - if (matchBind(*i, name, e2, pos)) map.set(name, makeRemoved()); - else abort(); /* can't happen */ - for (ATermIterator i(nrbnds); i; ++i) - if (matchBind(*i, name, e2, pos)) map.set(name, makeRemoved()); - else abort(); /* can't happen */ - return makeRec( - (ATermList) substitute(Substitution(&subs, &map), (ATerm) rbnds), - (ATermList) substitute(subs, (ATerm) nrbnds)); - } +Pos noPos; - if (ATgetType(e) == AT_APPL) { - AFun fun = ATgetAFun(e); - int arity = ATgetArity(fun); - ATerm args[arity]; - bool changed = false; - for (int i = 0; i < arity; ++i) { - ATerm arg = ATgetArgument(e, i); - args[i] = substitute(subs, arg); - if (args[i] != arg) changed = true; - } - - return changed ? (ATerm) ATmakeApplArray(fun, args) : e; - } +/* Computing levels/displacements for variables. */ - if (ATgetType(e) == AT_LIST) { - unsigned int len = ATgetLength((ATermList) e); - ATerm es[len]; - ATermIterator i((ATermList) e); - for (unsigned int j = 0; i; ++i, ++j) - es[j] = substitute(subs, *i); - ATermList out = ATempty; - for (unsigned int j = len; j; --j) - out = ATinsert(out, es[j - 1]); - return (ATerm) out; - } +void Expr::bindVars(const StaticEnv & env) +{ + abort(); +} - return e; +void ExprInt::bindVars(const StaticEnv & env) +{ } +void ExprString::bindVars(const StaticEnv & env) +{ +} -/* We use memoisation to prevent exponential complexity on heavily - shared ATerms (remember, an ATerm is a graph, not a tree!). Note - that using an STL set is fine here wrt to ATerm garbage collection - since all the ATerms in the set are already reachable from - somewhere else. */ -static void checkVarDefs2(set<Expr> & done, const ATermMap & defs, Expr e) +void ExprPath::bindVars(const StaticEnv & env) { - if (done.find(e) != done.end()) return; - done.insert(e); - - ATerm name, pos, value; - ATerm with, body; - ATermList rbnds, nrbnds; - Pattern pat; - - /* Closed terms don't have free variables, so we don't have to - check by definition. */ - if (matchClosed(e, value)) return; - - else if (matchVar(e, name)) { - if (!defs.get(name)) - throw EvalError(format("undefined variable `%1%'") - % aterm2String(name)); - } +} - else if (matchFunction(e, pat, body, pos)) { - ATermMap defs2(defs); - varsBoundByPattern(defs2, pat); - set<Expr> done2; - checkVarDefs2(done2, defs2, pat); - checkVarDefs2(done2, defs2, body); - } - - else if (matchRec(e, rbnds, nrbnds)) { - checkVarDefs2(done, defs, (ATerm) nrbnds); - ATermMap defs2(defs); - for (ATermIterator i(rbnds); i; ++i) { - if (!matchBind(*i, name, value, pos)) abort(); /* can't happen */ - defs2.set(name, (ATerm) ATempty); - } - for (ATermIterator i(nrbnds); i; ++i) { - if (!matchBind(*i, name, value, pos)) abort(); /* can't happen */ - defs2.set(name, (ATerm) ATempty); +void VarRef::bind(const StaticEnv & env) +{ + /* Check whether the variable appears in the environment. If so, + set its level and displacement. */ + const StaticEnv * curEnv; + unsigned int level; + int withLevel = -1; + for (curEnv = &env, level = 0; curEnv; curEnv = curEnv->up, level++) { + if (curEnv->isWith) { + if (withLevel == -1) withLevel = level; + } else { + StaticEnv::Vars::const_iterator i = curEnv->vars.find(name); + if (i != curEnv->vars.end()) { + fromWith = false; + this->level = level; + displ = i->second; + return; + } } - set<Expr> done2; - checkVarDefs2(done2, defs2, (ATerm) rbnds); } - else if (matchWith(e, with, body, pos)) { - /* We can't check the body without evaluating the definitions - (which is an arbitrary expression), so we don't do that - here but only when actually evaluating the `with'. */ - checkVarDefs2(done, defs, with); - } - - else if (ATgetType(e) == AT_APPL) { - int arity = ATgetArity(ATgetAFun(e)); - for (int i = 0; i < arity; ++i) - checkVarDefs2(done, defs, ATgetArgument(e, i)); - } + /* Otherwise, the variable must be obtained from the nearest + enclosing `with'. If there is no `with', then we can issue an + "undefined variable" error now. */ + if (withLevel == -1) throw EvalError(format("undefined variable `%1%'") % name); - else if (ATgetType(e) == AT_LIST) - for (ATermIterator i((ATermList) e); i; ++i) - checkVarDefs2(done, defs, *i); + fromWith = true; + this->level = withLevel; } - -void checkVarDefs(const ATermMap & defs, Expr e) +void ExprVar::bindVars(const StaticEnv & env) { - set<Expr> done; - checkVarDefs2(done, defs, e); + info.bind(env); } +void ExprSelect::bindVars(const StaticEnv & env) +{ + e->bindVars(env); +} -struct Canonicalise : TermFun +void ExprOpHasAttr::bindVars(const StaticEnv & env) { - ATerm operator () (ATerm e) - { - /* Remove position info. */ - ATerm path; - int line, column; - if (matchPos(e, path, line, column)) - return makeNoPos(); + e->bindVars(env); +} - /* Sort attribute sets. */ - ATermList _; - if (matchAttrs(e, _)) { - ATermMap attrs; - queryAllAttrs(e, attrs); - StringSet names; - for (ATermMap::const_iterator i = attrs.begin(); i != attrs.end(); ++i) - names.insert(aterm2String(i->key)); +void ExprAttrs::bindVars(const StaticEnv & env) +{ + if (recursive) { + StaticEnv newEnv(false, &env); + + unsigned int displ = 0; - ATermList attrs2 = ATempty; - for (StringSet::reverse_iterator i = names.rbegin(); i != names.rend(); ++i) - attrs2 = ATinsert(attrs2, - makeBind(toATerm(*i), attrs.get(toATerm(*i)), makeNoPos())); + foreach (ExprAttrs::Attrs::iterator, i, attrs) + newEnv.vars[i->first] = displ++; - return makeAttrs(attrs2); + foreach (list<Inherited>::iterator, i, inherited) { + newEnv.vars[i->first.name] = displ++; + i->first.bind(env); } - - return e; + + foreach (ExprAttrs::Attrs::iterator, i, attrs) + i->second.first->bindVars(newEnv); } -}; + else { + foreach (ExprAttrs::Attrs::iterator, i, attrs) + i->second.first->bindVars(env); -Expr canonicaliseExpr(Expr e) -{ - Canonicalise canonicalise; - return bottomupRewrite(canonicalise, e); + foreach (list<Inherited>::iterator, i, inherited) + i->first.bind(env); + } } - -Expr makeBool(bool b) +void ExprList::bindVars(const StaticEnv & env) { - return b ? eTrue : eFalse; + foreach (vector<Expr *>::iterator, i, elems) + (*i)->bindVars(env); } - -bool matchStr(Expr e, string & s, PathSet & context) +void ExprLambda::bindVars(const StaticEnv & env) { - ATermList l; - ATerm s_; - - if (!matchStr(e, s_, l)) return false; + StaticEnv newEnv(false, &env); + + unsigned int displ = 0; + + if (!arg.empty()) newEnv.vars[arg] = displ++; - s = aterm2String(s_); + if (matchAttrs) { + foreach (Formals::Formals_::iterator, i, formals->formals) + newEnv.vars[i->name] = displ++; - for (ATermIterator i(l); i; ++i) - context.insert(aterm2String(*i)); + foreach (Formals::Formals_::iterator, i, formals->formals) + if (i->def) i->def->bindVars(newEnv); + } - return true; + body->bindVars(newEnv); } +void ExprLet::bindVars(const StaticEnv & env) +{ + StaticEnv newEnv(false, &env); + + unsigned int displ = 0; + + foreach (ExprAttrs::Attrs::iterator, i, attrs->attrs) + newEnv.vars[i->first] = displ++; + + foreach (list<ExprAttrs::Inherited>::iterator, i, attrs->inherited) { + newEnv.vars[i->first.name] = displ++; + i->first.bind(env); + } -Expr makeStr(const string & s, const PathSet & context) + foreach (ExprAttrs::Attrs::iterator, i, attrs->attrs) + i->second.first->bindVars(newEnv); + + body->bindVars(newEnv); +} + +void ExprWith::bindVars(const StaticEnv & env) { - return makeStr(toATerm(s), toATermList(context)); + /* Does this `with' have an enclosing `with'? If so, record its + level so that `lookupVar' can look up variables in the previous + `with' if this one doesn't contain the desired attribute. */ + const StaticEnv * curEnv; + unsigned int level; + prevWith = 0; + for (curEnv = &env, level = 1; curEnv; curEnv = curEnv->up, level++) + if (curEnv->isWith) { + prevWith = level; + break; + } + + attrs->bindVars(env); + StaticEnv newEnv(true, &env); + body->bindVars(newEnv); } +void ExprIf::bindVars(const StaticEnv & env) +{ + cond->bindVars(env); + then->bindVars(env); + else_->bindVars(env); +} -string showType(Expr e) +void ExprAssert::bindVars(const StaticEnv & env) { - ATerm t1, t2; - ATermList l1; - ATermBlob b1; - int i1; - Pattern p1; - if (matchStr(e, t1, l1)) return "a string"; - if (matchPath(e, t1)) return "a path"; - if (matchNull(e)) return "null"; - if (matchInt(e, i1)) return "an integer"; - if (matchBool(e, t1)) return "a boolean"; - if (matchFunction(e, p1, t1, t2)) return "a function"; - if (matchAttrs(e, l1)) return "an attribute set"; - if (matchList(e, l1)) return "a list"; - if (matchPrimOp(e, i1, b1, l1)) return "a partially applied built-in function"; - return "an unknown type"; + cond->bindVars(env); + body->bindVars(env); } +void ExprOpNot::bindVars(const StaticEnv & env) +{ + e->bindVars(env); +} -string showValue(Expr e) +void ExprConcatStrings::bindVars(const StaticEnv & env) { - PathSet context; - string s; - ATerm s2; - int i; - if (matchStr(e, s, context)) { - string u; - for (string::iterator i = s.begin(); i != s.end(); ++i) - if (*i == '\"' || *i == '\\') u += "\\" + *i; - else if (*i == '\n') u += "\\n"; - else if (*i == '\r') u += "\\r"; - else if (*i == '\t') u += "\\t"; - else u += *i; - return "\"" + u + "\""; - } - if (matchPath(e, s2)) return aterm2String(s2); - if (matchNull(e)) return "null"; - if (matchInt(e, i)) return (format("%1%") % i).str(); - if (e == eTrue) return "true"; - if (e == eFalse) return "false"; - /* !!! incomplete */ - return "<unknown>"; + foreach (vector<Expr *>::iterator, i, *es) + (*i)->bindVars(env); } - + } diff --git a/src/libexpr/nixexpr.hh b/src/libexpr/nixexpr.hh index c7cdf46df9..1c72441b27 100644 --- a/src/libexpr/nixexpr.hh +++ b/src/libexpr/nixexpr.hh @@ -3,8 +3,7 @@ #include <map> -#include "aterm-map.hh" -#include "types.hh" +#include "symbol-table.hh" namespace nix { @@ -18,105 +17,254 @@ MakeError(Abort, EvalError) MakeError(TypeError, EvalError) -/* Nix expressions are represented as ATerms. The maximal sharing - property of the ATerm library allows us to implement caching of - normals forms efficiently. */ -typedef ATerm Expr; -typedef ATerm DefaultValue; -typedef ATerm Pos; -typedef ATerm Pattern; -typedef ATerm ATermBool; +/* Position objects. */ +struct Pos +{ + string file; + unsigned int line, column; + Pos() : line(0), column(0) { }; + Pos(const string & file, unsigned int line, unsigned int column) + : file(file), line(line), column(column) { }; +}; + +extern Pos noPos; + +std::ostream & operator << (std::ostream & str, const Pos & pos); -/* A STL vector of ATerms. Should be used with great care since it's - stored on the heap, and the elements are therefore not roots to the - ATerm garbage collector. */ -typedef vector<ATerm> ATermVector; +struct Env; +struct Value; +struct EvalState; +struct StaticEnv; -/* A substitution is a linked list of ATermMaps that map names to - identifiers. We use a list of ATermMaps rather than a single to - make it easy to grow or shrink a substitution when entering a - scope. */ -struct Substitution + +/* Abstract syntax of Nix expressions. */ + +struct Expr { - ATermMap * map; - const Substitution * prev; + virtual void show(std::ostream & str); + virtual void bindVars(const StaticEnv & env); + virtual void eval(EvalState & state, Env & env, Value & v); +}; - Substitution(const Substitution * prev, ATermMap * map) - { - this->prev = prev; - this->map = map; - } - - Expr lookup(Expr name) const - { - Expr x; - for (const Substitution * s(this); s; s = s->prev) - if ((x = s->map->get(name))) return x; - return 0; - } +std::ostream & operator << (std::ostream & str, Expr & e); + +#define COMMON_METHODS \ + void show(std::ostream & str); \ + void eval(EvalState & state, Env & env, Value & v); \ + void bindVars(const StaticEnv & env); + +struct ExprInt : Expr +{ + int n; + ExprInt(int n) : n(n) { }; + COMMON_METHODS }; +struct ExprString : Expr +{ + string s; + ExprString(const string & s) : s(s) { }; + COMMON_METHODS +}; -/* Show a position. */ -string showPos(ATerm pos); +/* Temporary class used during parsing of indented strings. */ +struct ExprIndStr : Expr +{ + string s; + ExprIndStr(const string & s) : s(s) { }; +}; -/* Generic bottomup traversal over ATerms. The traversal first - recursively descends into subterms, and then applies the given term - function to the resulting term. */ -struct TermFun +struct ExprPath : Expr { - virtual ~TermFun() { } - virtual ATerm operator () (ATerm e) = 0; + string s; + ExprPath(const string & s) : s(s) { }; + COMMON_METHODS }; -ATerm bottomupRewrite(TermFun & f, ATerm e); +struct VarRef +{ + Symbol name; -/* Query all attributes in an attribute set expression. The - expression must be in normal form. */ -void queryAllAttrs(Expr e, ATermMap & attrs, bool withPos = false); + /* Whether the variable comes from an environment (e.g. a rec, let + or function argument) or from a "with". */ + bool fromWith; + + /* In the former case, the value is obtained by going `level' + levels up from the current environment and getting the + `displ'th value in that environment. In the latter case, the + value is obtained by getting the attribute named `name' from + the attribute set stored in the environment that is `level' + levels up from the current one.*/ + unsigned int level; + unsigned int displ; + + VarRef(const Symbol & name) : name(name) { }; + void bind(const StaticEnv & env); +}; -/* Query a specific attribute from an attribute set expression. The - expression must be in normal form. */ -Expr queryAttr(Expr e, const string & name); -Expr queryAttr(Expr e, const string & name, ATerm & pos); +struct ExprVar : Expr +{ + VarRef info; + ExprVar(const Symbol & name) : info(name) { }; + COMMON_METHODS +}; -/* Create an attribute set expression from an Attrs value. */ -Expr makeAttrs(const ATermMap & attrs); +struct ExprSelect : Expr +{ + Expr * e; + Symbol name; + ExprSelect(Expr * e, const Symbol & name) : e(e), name(name) { }; + COMMON_METHODS +}; +struct ExprOpHasAttr : Expr +{ + Expr * e; + Symbol name; + ExprOpHasAttr(Expr * e, const Symbol & name) : e(e), name(name) { }; + COMMON_METHODS +}; -/* Perform a set of substitutions on an expression. */ -Expr substitute(const Substitution & subs, Expr e); +struct ExprAttrs : Expr +{ + bool recursive; + typedef std::pair<Expr *, Pos> Attr; + typedef std::pair<VarRef, Pos> Inherited; + typedef std::map<Symbol, Attr> Attrs; + Attrs attrs; + list<Inherited> inherited; + std::map<Symbol, Pos> attrNames; // used during parsing + ExprAttrs() : recursive(false) { }; + COMMON_METHODS +}; +struct ExprList : Expr +{ + std::vector<Expr *> elems; + ExprList() { }; + COMMON_METHODS +}; -/* Check whether all variables are defined in the given expression. - Throw an exception if this isn't the case. */ -void checkVarDefs(const ATermMap & def, Expr e); +struct Formal +{ + Symbol name; + Expr * def; + Formal(const Symbol & name, Expr * def) : name(name), def(def) { }; +}; +struct Formals +{ + typedef std::list<Formal> Formals_; + Formals_ formals; + std::set<Symbol> argNames; // used during parsing + bool ellipsis; +}; + +struct ExprLambda : Expr +{ + Pos pos; + Symbol arg; + bool matchAttrs; + Formals * formals; + Expr * body; + ExprLambda(const Pos & pos, const Symbol & arg, bool matchAttrs, Formals * formals, Expr * body) + : pos(pos), arg(arg), matchAttrs(matchAttrs), formals(formals), body(body) + { + if (!arg.empty() && formals && formals->argNames.find(arg) != formals->argNames.end()) + throw ParseError(format("duplicate formal function argument `%1%' at %2%") + % arg % pos); + }; + COMMON_METHODS +}; + +struct ExprLet : Expr +{ + ExprAttrs * attrs; + Expr * body; + ExprLet(ExprAttrs * attrs, Expr * body) : attrs(attrs), body(body) { }; + COMMON_METHODS +}; -/* Canonicalise a Nix expression by sorting attributes and removing - location information. */ -Expr canonicaliseExpr(Expr e); +struct ExprWith : Expr +{ + Pos pos; + Expr * attrs, * body; + unsigned int prevWith; + ExprWith(const Pos & pos, Expr * attrs, Expr * body) : pos(pos), attrs(attrs), body(body) { }; + COMMON_METHODS +}; +struct ExprIf : Expr +{ + Expr * cond, * then, * else_; + ExprIf(Expr * cond, Expr * then, Expr * else_) : cond(cond), then(then), else_(else_) { }; + COMMON_METHODS +}; -/* Create an expression representing a boolean. */ -Expr makeBool(bool b); +struct ExprAssert : Expr +{ + Pos pos; + Expr * cond, * body; + ExprAssert(const Pos & pos, Expr * cond, Expr * body) : pos(pos), cond(cond), body(body) { }; + COMMON_METHODS +}; +struct ExprOpNot : Expr +{ + Expr * e; + ExprOpNot(Expr * e) : e(e) { }; + COMMON_METHODS +}; -/* Manipulation of Str() nodes. Note: matchStr() does not clear - context! */ -bool matchStr(Expr e, string & s, PathSet & context); +#define MakeBinOp(name, s) \ + struct Expr##name : Expr \ + { \ + Expr * e1, * e2; \ + Expr##name(Expr * e1, Expr * e2) : e1(e1), e2(e2) { }; \ + void show(std::ostream & str) \ + { \ + str << *e1 << " " s " " << *e2; \ + } \ + void bindVars(const StaticEnv & env) \ + { \ + e1->bindVars(env); e2->bindVars(env); \ + } \ + void eval(EvalState & state, Env & env, Value & v); \ + }; + +MakeBinOp(App, "") +MakeBinOp(OpEq, "==") +MakeBinOp(OpNEq, "!=") +MakeBinOp(OpAnd, "&&") +MakeBinOp(OpOr, "||") +MakeBinOp(OpImpl, "->") +MakeBinOp(OpUpdate, "//") +MakeBinOp(OpConcatLists, "++") + +struct ExprConcatStrings : Expr +{ + vector<Expr *> * es; + ExprConcatStrings(vector<Expr *> * es) : es(es) { }; + COMMON_METHODS +}; -Expr makeStr(const string & s, const PathSet & context = PathSet()); +/* Static environments are used to map variable names onto (level, + displacement) pairs used to obtain the value of the variable at + runtime. */ +struct StaticEnv +{ + bool isWith; + const StaticEnv * up; + typedef std::map<Symbol, unsigned int> Vars; + Vars vars; + StaticEnv(bool isWith, const StaticEnv * up) : isWith(isWith), up(up) { }; +}; -/* Showing types, values. */ -string showType(Expr e); -string showValue(Expr e); - } diff --git a/src/libexpr/parser.hh b/src/libexpr/parser.hh index 334822b5e0..c8c8ad8090 100644 --- a/src/libexpr/parser.hh +++ b/src/libexpr/parser.hh @@ -8,12 +8,11 @@ namespace nix { /* Parse a Nix expression from the specified file. If `path' refers - to a directory, the "/default.nix" is appended. */ -Expr parseExprFromFile(EvalState & state, Path path); + to a directory, then "/default.nix" is appended. */ +Expr * parseExprFromFile(EvalState & state, Path path); /* Parse a Nix expression from the specified string. */ -Expr parseExprFromString(EvalState & state, const string & s, - const Path & basePath); +Expr * parseExprFromString(EvalState & state, const string & s, const Path & basePath); } diff --git a/src/libexpr/parser.y b/src/libexpr/parser.y index 8706ce0254..7236bab19c 100644 --- a/src/libexpr/parser.y +++ b/src/libexpr/parser.y @@ -20,16 +20,14 @@ #include <stdlib.h> #include <string.h> -#include "aterm.hh" #include "util.hh" +#include "nixexpr.hh" + #include "parser-tab.hh" #include "lexer-tab.hh" #define YYSTYPE YYSTYPE // workaround a bug in Bison 2.4 -#include "nixexpr.hh" -#include "nixexpr-ast.hh" - using namespace nix; @@ -39,145 +37,85 @@ namespace nix { struct ParseData { - Expr result; + SymbolTable & symbols; + Expr * result; Path basePath; Path path; string error; + Symbol sLetBody; + ParseData(SymbolTable & symbols) + : symbols(symbols) + , sLetBody(symbols.create("<let-body>")) + { }; }; - -static string showAttrPath(ATermList attrPath) + +static string showAttrPath(const vector<Symbol> & attrPath) { string s; - for (ATermIterator i(attrPath); i; ++i) { + foreach (vector<Symbol>::const_iterator, i, attrPath) { if (!s.empty()) s += '.'; - s += aterm2String(*i); + s += *i; } return s; } - - -struct Tree -{ - Expr leaf; ATerm pos; bool recursive; - typedef std::map<ATerm, Tree> Children; - Children children; - Tree() { leaf = 0; recursive = true; } -}; -static ATermList buildAttrs(const Tree & t, ATermList & nonrec) +static void dupAttr(const vector<Symbol> & attrPath, const Pos & pos, const Pos & prevPos) { - ATermList res = ATempty; - for (Tree::Children::const_reverse_iterator i = t.children.rbegin(); - i != t.children.rend(); ++i) - if (!i->second.recursive) - nonrec = ATinsert(nonrec, makeBind(i->first, i->second.leaf, i->second.pos)); - else - res = ATinsert(res, i->second.leaf - ? makeBind(i->first, i->second.leaf, i->second.pos) - : makeBind(i->first, makeAttrs(buildAttrs(i->second, nonrec)), makeNoPos())); - return res; + throw ParseError(format("attribute `%1%' at %2% already defined at %3%") + % showAttrPath(attrPath) % pos % prevPos); } -static Expr fixAttrs(bool recursive, ATermList as) +static void dupAttr(Symbol attr, const Pos & pos, const Pos & prevPos) { - Tree attrs; - - /* This ATermMap is needed to ensure that the `leaf' fields in the - Tree nodes are not garbage collected. */ - ATermMap gcRoots; - - for (ATermIterator i(as); i; ++i) { - ATermList names, attrPath; Expr src, e; ATerm name, pos; - - if (matchInherit(*i, src, names, pos)) { - bool fromScope = matchScope(src); - for (ATermIterator j(names); j; ++j) { - if (attrs.children.find(*j) != attrs.children.end()) - throw ParseError(format("duplicate definition of attribute `%1%' at %2%") - % showAttrPath(ATmakeList1(*j)) % showPos(pos)); - Tree & t(attrs.children[*j]); - Expr leaf = fromScope ? makeVar(*j) : makeSelect(src, *j); - gcRoots.set(leaf, leaf); - t.leaf = leaf; - t.pos = pos; - if (recursive && fromScope) t.recursive = false; - } - } - - else if (matchBindAttrPath(*i, attrPath, e, pos)) { - - Tree * t(&attrs); - - for (ATermIterator j(attrPath); j; ) { - name = *j; ++j; - if (t->leaf) throw ParseError(format("attribute set containing `%1%' at %2% already defined at %3%") - % showAttrPath(attrPath) % showPos(pos) % showPos (t->pos)); - t = &(t->children[name]); - } - - if (t->leaf) - throw ParseError(format("duplicate definition of attribute `%1%' at %2% and %3%") - % showAttrPath(attrPath) % showPos(pos) % showPos (t->pos)); - if (!t->children.empty()) - throw ParseError(format("duplicate definition of attribute `%1%' at %2%") - % showAttrPath(attrPath) % showPos(pos)); - - t->leaf = e; t->pos = pos; - } - - else abort(); /* can't happen */ - } - - ATermList nonrec = ATempty; - ATermList rec = buildAttrs(attrs, nonrec); - - return recursive ? makeRec(rec, nonrec) : makeAttrs(rec); + vector<Symbol> attrPath; attrPath.push_back(attr); + throw ParseError(format("attribute `%1%' at %2% already defined at %3%") + % showAttrPath(attrPath) % pos % prevPos); } + - -static void checkPatternVars(ATerm pos, ATermMap & map, Pattern pat) +static void addAttr(ExprAttrs * attrs, const vector<Symbol> & attrPath, + Expr * e, const Pos & pos) { - ATerm name; - ATermList formals; - Pattern pat1, pat2; - ATermBool ellipsis; - if (matchVarPat(pat, name)) { - if (map.get(name)) - throw ParseError(format("duplicate formal function argument `%1%' at %2%") - % aterm2String(name) % showPos(pos)); - map.set(name, name); - } - else if (matchAttrsPat(pat, formals, ellipsis)) { - for (ATermIterator i(formals); i; ++i) { - ATerm d1; - if (!matchFormal(*i, name, d1)) abort(); - if (map.get(name)) - throw ParseError(format("duplicate formal function argument `%1%' at %2%") - % aterm2String(name) % showPos(pos)); - map.set(name, name); + unsigned int n = 0; + foreach (vector<Symbol>::const_iterator, i, attrPath) { + n++; + ExprAttrs::Attrs::iterator j = attrs->attrs.find(*i); + if (j != attrs->attrs.end()) { + ExprAttrs * attrs2 = dynamic_cast<ExprAttrs *>(j->second.first); + if (!attrs2 || n == attrPath.size()) dupAttr(attrPath, pos, j->second.second); + attrs = attrs2; + } else { + if (attrs->attrNames.find(*i) != attrs->attrNames.end()) + dupAttr(attrPath, pos, attrs->attrNames[*i]); + attrs->attrNames[*i] = pos; + if (n == attrPath.size()) + attrs->attrs[*i] = ExprAttrs::Attr(e, pos); + else { + ExprAttrs * nested = new ExprAttrs; + attrs->attrs[*i] = ExprAttrs::Attr(nested, pos); + attrs = nested; + } } } - else if (matchAtPat(pat, pat1, pat2)) { - checkPatternVars(pos, map, pat1); - checkPatternVars(pos, map, pat2); - } - else abort(); } -static void checkPatternVars(ATerm pos, Pattern pat) +static void addFormal(const Pos & pos, Formals * formals, const Formal & formal) { - ATermMap map; - checkPatternVars(pos, map, pat); + if (formals->argNames.find(formal.name) != formals->argNames.end()) + throw ParseError(format("duplicate formal function argument `%1%' at %2%") + % formal.name % pos); + formals->formals.push_front(formal); + formals->argNames.insert(formal.name); } -static Expr stripIndentation(ATermList es) +static Expr * stripIndentation(vector<Expr *> & es) { - if (es == ATempty) return makeStr(""); + if (es.empty()) return new ExprString(""); /* Figure out the minimum indentation. Note that by design whitespace-only final lines are not taken into account. (So @@ -185,9 +123,9 @@ static Expr stripIndentation(ATermList es) bool atStartOfLine = true; /* = seen only whitespace in the current line */ unsigned int minIndent = 1000000; unsigned int curIndent = 0; - ATerm e; - for (ATermIterator i(es); i; ++i) { - if (!matchIndStr(*i, e)) { + foreach (vector<Expr *>::iterator, i, es) { + ExprIndStr * e = dynamic_cast<ExprIndStr *>(*i); + if (!e) { /* Anti-quotations end the current start-of-line whitespace. */ if (atStartOfLine) { atStartOfLine = false; @@ -195,12 +133,11 @@ static Expr stripIndentation(ATermList es) } continue; } - string s = aterm2String(e); - for (unsigned int j = 0; j < s.size(); ++j) { + for (unsigned int j = 0; j < e->s.size(); ++j) { if (atStartOfLine) { - if (s[j] == ' ') + if (e->s[j] == ' ') curIndent++; - else if (s[j] == '\n') { + else if (e->s[j] == '\n') { /* Empty line, doesn't influence minimum indentation. */ curIndent = 0; @@ -208,7 +145,7 @@ static Expr stripIndentation(ATermList es) atStartOfLine = false; if (curIndent < minIndent) minIndent = curIndent; } - } else if (s[j] == '\n') { + } else if (e->s[j] == '\n') { atStartOfLine = true; curIndent = 0; } @@ -216,37 +153,37 @@ static Expr stripIndentation(ATermList es) } /* Strip spaces from each line. */ - ATermList es2 = ATempty; + vector<Expr *> * es2 = new vector<Expr *>; atStartOfLine = true; unsigned int curDropped = 0; - unsigned int n = ATgetLength(es); - for (ATermIterator i(es); i; ++i, --n) { - if (!matchIndStr(*i, e)) { + unsigned int n = es.size(); + for (vector<Expr *>::iterator i = es.begin(); i != es.end(); ++i, --n) { + ExprIndStr * e = dynamic_cast<ExprIndStr *>(*i); + if (!e) { atStartOfLine = false; curDropped = 0; - es2 = ATinsert(es2, *i); + es2->push_back(*i); continue; } - string s = aterm2String(e); string s2; - for (unsigned int j = 0; j < s.size(); ++j) { + for (unsigned int j = 0; j < e->s.size(); ++j) { if (atStartOfLine) { - if (s[j] == ' ') { + if (e->s[j] == ' ') { if (curDropped++ >= minIndent) - s2 += s[j]; + s2 += e->s[j]; } - else if (s[j] == '\n') { + else if (e->s[j] == '\n') { curDropped = 0; - s2 += s[j]; + s2 += e->s[j]; } else { atStartOfLine = false; curDropped = 0; - s2 += s[j]; + s2 += e->s[j]; } } else { - s2 += s[j]; - if (s[j] == '\n') atStartOfLine = true; + s2 += e->s[j]; + if (e->s[j] == '\n') atStartOfLine = true; } } @@ -257,11 +194,11 @@ static Expr stripIndentation(ATermList es) if (p != string::npos && s2.find_first_not_of(' ', p + 1) == string::npos) s2 = string(s2, 0, p + 1); } - - es2 = ATinsert(es2, makeStr(s2)); + + es2->push_back(new ExprString(s2)); } - return makeConcatStrings(ATreverse(es2)); + return new ExprConcatStrings(es2); } @@ -269,13 +206,12 @@ void backToString(yyscan_t scanner); void backToIndString(yyscan_t scanner); -static Pos makeCurPos(YYLTYPE * loc, ParseData * data) +static Pos makeCurPos(const YYLTYPE & loc, ParseData * data) { - return makePos(toATerm(data->path), - loc->first_line, loc->first_column); + return Pos(data->path, loc.first_line, loc.first_column); } -#define CUR_POS makeCurPos(yylocp, data) +#define CUR_POS makeCurPos(*yylocp, data) } @@ -283,29 +219,10 @@ static Pos makeCurPos(YYLTYPE * loc, ParseData * data) void yyerror(YYLTYPE * loc, yyscan_t scanner, ParseData * data, const char * error) { - data->error = (format("%1%, at `%2%':%3%:%4%") - % error % data->path % loc->first_line % loc->first_column).str(); -} - - -/* Make sure that the parse stack is scanned by the ATerm garbage - collector. */ -static void * mallocAndProtect(size_t size) -{ - void * p = malloc(size); - if (p) ATprotectMemory(p, size); - return p; -} - -static void freeAndUnprotect(void * p) -{ - ATunprotectMemory(p); - free(p); + data->error = (format("%1%, at %2%") + % error % makeCurPos(*loc, data)).str(); } -#define YYMALLOC mallocAndProtect -#define YYFREE freeAndUnprotect - #endif @@ -313,20 +230,32 @@ static void freeAndUnprotect(void * p) %} %union { - ATerm t; - ATermList ts; - struct { - ATermList formals; - bool ellipsis; - } formals; + nix::Expr * e; + nix::ExprList * list; + nix::ExprAttrs * attrs; + nix::Formals * formals; + nix::Formal * formal; + int n; + char * id; // !!! -> Symbol + char * path; + char * uri; + std::vector<nix::Symbol> * ids; + std::vector<nix::Expr *> * string_parts; } -%type <t> start expr expr_function expr_if expr_op -%type <t> expr_app expr_select expr_simple bind inheritsrc formal -%type <t> pattern pattern2 -%type <ts> binds ids attrpath expr_list string_parts ind_string_parts +%type <e> start expr expr_function expr_if expr_op +%type <e> expr_app expr_select expr_simple +%type <list> expr_list +%type <attrs> binds %type <formals> formals -%token <t> ID INT STR IND_STR PATH URI +%type <formal> formal +%type <ids> ids attrpath +%type <string_parts> string_parts ind_string_parts +%token <id> ID ATTRPATH +%token <e> STR IND_STR +%token <n> INT +%token <path> PATH +%token <uri> URI %token IF THEN ELSE ASSERT WITH LET IN REC INHERIT EQ NEQ AND OR IMPL %token DOLLAR_CURLY /* == ${ */ %token IND_STRING_OPEN IND_STRING_CLOSE @@ -350,163 +279,172 @@ start: expr { data->result = $1; }; expr: expr_function; expr_function - : pattern ':' expr_function - { checkPatternVars(CUR_POS, $1); $$ = makeFunction($1, $3, CUR_POS); } + : ID ':' expr_function + { $$ = new ExprLambda(CUR_POS, data->symbols.create($1), false, 0, $3); } + | '{' formals '}' ':' expr_function + { $$ = new ExprLambda(CUR_POS, data->symbols.create(""), true, $2, $5); } + | '{' formals '}' '@' ID ':' expr_function + { $$ = new ExprLambda(CUR_POS, data->symbols.create($5), true, $2, $7); } + | ID '@' '{' formals '}' ':' expr_function + { $$ = new ExprLambda(CUR_POS, data->symbols.create($1), true, $4, $7); } | ASSERT expr ';' expr_function - { $$ = makeAssert($2, $4, CUR_POS); } + { $$ = new ExprAssert(CUR_POS, $2, $4); } | WITH expr ';' expr_function - { $$ = makeWith($2, $4, CUR_POS); } + { $$ = new ExprWith(CUR_POS, $2, $4); } | LET binds IN expr_function - { $$ = makeSelect(fixAttrs(true, ATinsert($2, makeBindAttrPath(ATmakeList1(toATerm("<let-body>")), $4, CUR_POS))), toATerm("<let-body>")); } + { $$ = new ExprLet($2, $4); } | expr_if ; expr_if - : IF expr THEN expr ELSE expr - { $$ = makeIf($2, $4, $6); } + : IF expr THEN expr ELSE expr { $$ = new ExprIf($2, $4, $6); } | expr_op ; expr_op - : '!' expr_op %prec NEG { $$ = makeOpNot($2); } - | expr_op EQ expr_op { $$ = makeOpEq($1, $3); } - | expr_op NEQ expr_op { $$ = makeOpNEq($1, $3); } - | expr_op AND expr_op { $$ = makeOpAnd($1, $3); } - | expr_op OR expr_op { $$ = makeOpOr($1, $3); } - | expr_op IMPL expr_op { $$ = makeOpImpl($1, $3); } - | expr_op UPDATE expr_op { $$ = makeOpUpdate($1, $3); } - | expr_op '~' expr_op { $$ = makeSubPath($1, $3); } - | expr_op '?' ID { $$ = makeOpHasAttr($1, $3); } - | expr_op '+' expr_op { $$ = makeOpPlus($1, $3); } - | expr_op CONCAT expr_op { $$ = makeOpConcat($1, $3); } + : '!' expr_op %prec NEG { $$ = new ExprOpNot($2); } + | expr_op EQ expr_op { $$ = new ExprOpEq($1, $3); } + | expr_op NEQ expr_op { $$ = new ExprOpNEq($1, $3); } + | expr_op AND expr_op { $$ = new ExprOpAnd($1, $3); } + | expr_op OR expr_op { $$ = new ExprOpOr($1, $3); } + | expr_op IMPL expr_op { $$ = new ExprOpImpl($1, $3); } + | expr_op UPDATE expr_op { $$ = new ExprOpUpdate($1, $3); } + | expr_op '?' ID { $$ = new ExprOpHasAttr($1, data->symbols.create($3)); } + | expr_op '+' expr_op + { vector<Expr *> * l = new vector<Expr *>; + l->push_back($1); + l->push_back($3); + $$ = new ExprConcatStrings(l); + } + | expr_op CONCAT expr_op { $$ = new ExprOpConcatLists($1, $3); } | expr_app ; expr_app : expr_app expr_select - { $$ = makeCall($1, $2); } + { $$ = new ExprApp($1, $2); } | expr_select { $$ = $1; } ; expr_select : expr_select '.' ID - { $$ = makeSelect($1, $3); } + { $$ = new ExprSelect($1, data->symbols.create($3)); } | expr_simple { $$ = $1; } ; expr_simple - : ID { $$ = makeVar($1); } - | INT { $$ = makeInt(ATgetInt((ATermInt) $1)); } + : ID { $$ = new ExprVar(data->symbols.create($1)); } + | INT { $$ = new ExprInt($1); } | '"' string_parts '"' { /* For efficiency, and to simplify parse trees a bit. */ - if ($2 == ATempty) $$ = makeStr(toATerm(""), ATempty); - else if (ATgetNext($2) == ATempty) $$ = ATgetFirst($2); - else $$ = makeConcatStrings(ATreverse($2)); + if ($2->empty()) $$ = new ExprString(""); + else if ($2->size() == 1) $$ = $2->front(); + else $$ = new ExprConcatStrings($2); } | IND_STRING_OPEN ind_string_parts IND_STRING_CLOSE { - $$ = stripIndentation(ATreverse($2)); + $$ = stripIndentation(*$2); } - | PATH { $$ = makePath(toATerm(absPath(aterm2String($1), data->basePath))); } - | URI { $$ = makeStr($1, ATempty); } + | PATH { $$ = new ExprPath(absPath($1, data->basePath)); } + | URI { $$ = new ExprString($1); } | '(' expr ')' { $$ = $2; } /* Let expressions `let {..., body = ...}' are just desugared into `(rec {..., body = ...}).body'. */ | LET '{' binds '}' - { $$ = makeSelect(fixAttrs(true, $3), toATerm("body")); } + { $3->recursive = true; $$ = new ExprSelect($3, data->symbols.create("body")); } | REC '{' binds '}' - { $$ = fixAttrs(true, $3); } + { $3->recursive = true; $$ = $3; } | '{' binds '}' - { $$ = fixAttrs(false, $2); } - | '[' expr_list ']' { $$ = makeList(ATreverse($2)); } + { $$ = $2; } + | '[' expr_list ']' { $$ = $2; } ; string_parts - : string_parts STR { $$ = ATinsert($1, $2); } - | string_parts DOLLAR_CURLY expr '}' { backToString(scanner); $$ = ATinsert($1, $3); } - | { $$ = ATempty; } + : string_parts STR { $$ = $1; $1->push_back($2); } + | string_parts DOLLAR_CURLY expr '}' { backToString(scanner); $$ = $1; $1->push_back($3); } + | { $$ = new vector<Expr *>; } ; ind_string_parts - : ind_string_parts IND_STR { $$ = ATinsert($1, $2); } - | ind_string_parts DOLLAR_CURLY expr '}' { backToIndString(scanner); $$ = ATinsert($1, $3); } - | { $$ = ATempty; } - ; - -pattern - : pattern2 '@' pattern { $$ = makeAtPat($1, $3); } - | pattern2 - ; - -pattern2 - : ID { $$ = makeVarPat($1); } - | '{' formals '}' { $$ = makeAttrsPat($2.formals, $2.ellipsis ? eTrue : eFalse); } + : ind_string_parts IND_STR { $$ = $1; $1->push_back($2); } + | ind_string_parts DOLLAR_CURLY expr '}' { backToIndString(scanner); $$ = $1; $1->push_back($3); } + | { $$ = new vector<Expr *>; } ; binds - : binds bind { $$ = ATinsert($1, $2); } - | { $$ = ATempty; } - ; - -bind - : attrpath '=' expr ';' - { $$ = makeBindAttrPath(ATreverse($1), $3, CUR_POS); } - | INHERIT inheritsrc ids ';' - { $$ = makeInherit($2, $3, CUR_POS); } + : binds attrpath '=' expr ';' { $$ = $1; addAttr($$, *$2, $4, makeCurPos(@2, data)); } + | binds INHERIT ids ';' + { $$ = $1; + foreach (vector<Symbol>::iterator, i, *$3) { + if ($$->attrNames.find(*i) != $$->attrNames.end()) + dupAttr(*i, makeCurPos(@3, data), $$->attrNames[*i]); + Pos pos = makeCurPos(@3, data); + $$->inherited.push_back(ExprAttrs::Inherited(*i, pos)); + $$->attrNames[*i] = pos; + } + } + | binds INHERIT '(' expr ')' ids ';' + { $$ = $1; + /* !!! Should ensure sharing of the expression in $4. */ + foreach (vector<Symbol>::iterator, i, *$6) { + if ($$->attrNames.find(*i) != $$->attrNames.end()) + dupAttr(*i, makeCurPos(@6, data), $$->attrNames[*i]); + $$->attrs[*i] = ExprAttrs::Attr(new ExprSelect($4, *i), makeCurPos(@6, data)); + $$->attrNames[*i] = makeCurPos(@6, data); + }} + + | { $$ = new ExprAttrs; } ; -inheritsrc - : '(' expr ')' { $$ = $2; } - | { $$ = makeScope(); } +ids + : ids ID { $$ = $1; $1->push_back(data->symbols.create($2)); /* !!! dangerous */ } + | { $$ = new vector<Symbol>; } ; -ids: ids ID { $$ = ATinsert($1, $2); } | { $$ = ATempty; }; - attrpath - : attrpath '.' ID { $$ = ATinsert($1, $3); } - | ID { $$ = ATmakeList1($1); } + : attrpath '.' ID { $$ = $1; $1->push_back(data->symbols.create($3)); } + | ID { $$ = new vector<Symbol>; $$->push_back(data->symbols.create($1)); } ; expr_list - : expr_list expr_select { $$ = ATinsert($1, $2); } - | { $$ = ATempty; } + : expr_list expr_select { $$ = $1; $1->elems.push_back($2); /* !!! dangerous */ } + | { $$ = new ExprList; } ; formals - : formal ',' formals /* !!! right recursive */ - { $$.formals = ATinsert($3.formals, $1); $$.ellipsis = $3.ellipsis; } + : formal ',' formals + { $$ = $3; addFormal(CUR_POS, $$, *$1); } | formal - { $$.formals = ATinsert(ATempty, $1); $$.ellipsis = false; } + { $$ = new Formals; addFormal(CUR_POS, $$, *$1); $$->ellipsis = false; } | - { $$.formals = ATempty; $$.ellipsis = false; } + { $$ = new Formals; $$->ellipsis = false; } | ELLIPSIS - { $$.formals = ATempty; $$.ellipsis = true; } + { $$ = new Formals; $$->ellipsis = true; } ; formal - : ID { $$ = makeFormal($1, makeNoDefaultValue()); } - | ID '?' expr { $$ = makeFormal($1, makeDefaultValue($3)); } + : ID { $$ = new Formal(data->symbols.create($1), 0); } + | ID '?' expr { $$ = new Formal(data->symbols.create($1), $3); } ; %% -#include "eval.hh" - #include <sys/types.h> #include <sys/stat.h> #include <fcntl.h> #include <unistd.h> +#include <eval.hh> + namespace nix { -static Expr parse(EvalState & state, - const char * text, const Path & path, - const Path & basePath) +static Expr * parse(EvalState & state, const char * text, + const Path & path, const Path & basePath) { yyscan_t scanner; - ParseData data; + ParseData data(state.symbols); data.basePath = basePath; data.path = path; @@ -518,7 +456,7 @@ static Expr parse(EvalState & state, if (res) throw ParseError(data.error); try { - checkVarDefs(state.primOps, data.result); + data.result->bindVars(state.staticBaseEnv); } catch (Error & e) { throw ParseError(format("%1%, in `%2%'") % e.msg() % path); } @@ -527,16 +465,10 @@ static Expr parse(EvalState & state, } -Expr parseExprFromFile(EvalState & state, Path path) +Expr * parseExprFromFile(EvalState & state, Path path) { assert(path[0] == '/'); -#if 0 - /* Perhaps this is already an imploded parse tree? */ - Expr e = ATreadFromNamedFile(path.c_str()); - if (e) return e; -#endif - /* If `path' is a symlink, follow it. This is so that relative path references work. */ struct stat st; @@ -558,7 +490,7 @@ Expr parseExprFromFile(EvalState & state, Path path) } -Expr parseExprFromString(EvalState & state, +Expr * parseExprFromString(EvalState & state, const string & s, const Path & basePath) { return parse(state, s.c_str(), "(string)", basePath); diff --git a/src/libexpr/primops.cc b/src/libexpr/primops.cc index 7dddc91a86..a7e7bcdc86 100644 --- a/src/libexpr/primops.cc +++ b/src/libexpr/primops.cc @@ -4,8 +4,7 @@ #include "store-api.hh" #include "util.hh" #include "archive.hh" -#include "expr-to-xml.hh" -#include "nixexpr-ast.hh" +#include "value-to-xml.hh" #include "parser.hh" #include "names.hh" @@ -14,87 +13,23 @@ #include <unistd.h> #include <algorithm> +#include <cstring> namespace nix { /************************************************************* - * Constants - *************************************************************/ - - -static Expr prim_builtins(EvalState & state, const ATermVector & args) -{ - /* Return an attribute set containing all primops. This allows - Nix expressions to test for new primops and take appropriate - action if they're not available. For instance, rather than - calling a primop `foo' directly, they could say `if builtins ? - foo then builtins.foo ... else ...'. */ - - ATermMap builtins(state.primOps.size()); - - for (ATermMap::const_iterator i = state.primOps.begin(); - i != state.primOps.end(); ++i) - { - string name = aterm2String(i->key); - if (string(name, 0, 2) == "__") - name = string(name, 2); - /* !!! should use makePrimOp here, I guess. */ - builtins.set(toATerm(name), makeAttrRHS(makeVar(i->key), makeNoPos())); - } - - return makeAttrs(builtins); -} - - -/* Boolean constructors. */ -static Expr prim_true(EvalState & state, const ATermVector & args) -{ - return eTrue; -} - - -static Expr prim_false(EvalState & state, const ATermVector & args) -{ - return eFalse; -} - - -/* Return the null value. */ -static Expr prim_null(EvalState & state, const ATermVector & args) -{ - return makeNull(); -} - - -/* Return a string constant representing the current platform. Note! - that differs between platforms, so Nix expressions using - `__currentSystem' can evaluate to different values on different - platforms. */ -static Expr prim_currentSystem(EvalState & state, const ATermVector & args) -{ - return makeStr(thisSystem); -} - - -static Expr prim_currentTime(EvalState & state, const ATermVector & args) -{ - return ATmake("Int(<int>)", time(0)); -} - - -/************************************************************* * Miscellaneous *************************************************************/ /* Load and evaluate an expression from path specified by the argument. */ -static Expr prim_import(EvalState & state, const ATermVector & args) +static void prim_import(EvalState & state, Value * * args, Value & v) { PathSet context; - Path path = coerceToPath(state, args[0], context); + Path path = state.coerceToPath(*args[0], context); for (PathSet::iterator i = context.begin(); i != context.end(); ++i) { assert(isStorePath(*i)); @@ -105,127 +40,172 @@ static Expr prim_import(EvalState & state, const ATermVector & args) store->buildDerivations(singleton<PathSet>(*i)); } - return evalFile(state, path); + state.evalFile(path, v); } /* Determine whether the argument is the null value. */ -static Expr prim_isNull(EvalState & state, const ATermVector & args) +static void prim_isNull(EvalState & state, Value * * args, Value & v) { - return makeBool(matchNull(evalExpr(state, args[0]))); + state.forceValue(*args[0]); + mkBool(v, args[0]->type == tNull); } /* Determine whether the argument is a function. */ -static Expr prim_isFunction(EvalState & state, const ATermVector & args) +static void prim_isFunction(EvalState & state, Value * * args, Value & v) { - Expr e = evalExpr(state, args[0]); - Pattern pat; - ATerm body, pos; - return makeBool(matchFunction(e, pat, body, pos)); + state.forceValue(*args[0]); + mkBool(v, args[0]->type == tLambda); } + /* Determine whether the argument is an Int. */ -static Expr prim_isInt(EvalState & state, const ATermVector & args) +static void prim_isInt(EvalState & state, Value * * args, Value & v) { - int i; - return makeBool(matchInt(evalExpr(state, args[0]), i)); + state.forceValue(*args[0]); + mkBool(v, args[0]->type == tInt); } + /* Determine whether the argument is an String. */ -static Expr prim_isString(EvalState & state, const ATermVector & args) +static void prim_isString(EvalState & state, Value * * args, Value & v) { - string s; - PathSet l; - return makeBool(matchStr(evalExpr(state, args[0]), s, l)); + state.forceValue(*args[0]); + mkBool(v, args[0]->type == tString); } + /* Determine whether the argument is an Bool. */ -static Expr prim_isBool(EvalState & state, const ATermVector & args) +static void prim_isBool(EvalState & state, Value * * args, Value & v) { - ATermBool b; - return makeBool(matchBool(evalExpr(state, args[0]), b)); + state.forceValue(*args[0]); + mkBool(v, args[0]->type == tBool); } -static Expr prim_genericClosure(EvalState & state, const ATermVector & args) + +struct CompareValues +{ + bool operator () (const Value & v1, const Value & v2) const + { + if (v1.type != v2.type) + throw EvalError("cannot compare values of different types"); + switch (v1.type) { + case tInt: + return v1.integer < v2.integer; + case tString: + return strcmp(v1.string.s, v2.string.s) < 0; + case tPath: + return strcmp(v1.path, v2.path) < 0; + default: + throw EvalError(format("cannot compare %1% with %2%") % showType(v1) % showType(v2)); + } + } +}; + + +static void prim_genericClosure(EvalState & state, Value * * args, Value & v) { startNest(nest, lvlDebug, "finding dependencies"); - Expr attrs = evalExpr(state, args[0]); + state.forceAttrs(*args[0]); /* Get the start set. */ - Expr startSet = queryAttr(attrs, "startSet"); - if (!startSet) throw EvalError("attribute `startSet' required"); - ATermList startSet2 = evalList(state, startSet); + Bindings::iterator startSet = + args[0]->attrs->find(state.symbols.create("startSet")); + if (startSet == args[0]->attrs->end()) + throw EvalError("attribute `startSet' required"); + state.forceList(startSet->second.value); - set<Expr> workSet; // !!! gc roots - for (ATermIterator i(startSet2); i; ++i) workSet.insert(*i); + list<Value *> workSet; + for (unsigned int n = 0; n < startSet->second.value.list.length; ++n) + workSet.push_back(startSet->second.value.list.elems[n]); /* Get the operator. */ - Expr op = queryAttr(attrs, "operator"); - if (!op) throw EvalError("attribute `operator' required"); - + Bindings::iterator op = + args[0]->attrs->find(state.symbols.create("operator")); + if (op == args[0]->attrs->end()) + throw EvalError("attribute `operator' required"); + state.forceValue(op->second.value); + /* Construct the closure by applying the operator to element of `workSet', adding the result to `workSet', continuing until no new elements are found. */ - ATermList res = ATempty; - set<Expr> doneKeys; // !!! gc roots + list<Value> res; + set<Value, CompareValues> doneKeys; while (!workSet.empty()) { - Expr e = *(workSet.begin()); - workSet.erase(e); + Value * e = *(workSet.begin()); + workSet.pop_front(); - e = strictEvalExpr(state, e); + state.forceAttrs(*e); - Expr key = queryAttr(e, "key"); - if (!key) throw EvalError("attribute `key' required"); + Bindings::iterator key = + e->attrs->find(state.symbols.create("key")); + if (key == e->attrs->end()) + throw EvalError("attribute `key' required"); + state.forceValue(key->second.value); - if (doneKeys.find(key) != doneKeys.end()) continue; - doneKeys.insert(key); - res = ATinsert(res, e); + if (doneKeys.find(key->second.value) != doneKeys.end()) continue; + doneKeys.insert(key->second.value); + res.push_back(*e); /* Call the `operator' function with `e' as argument. */ - ATermList res = evalList(state, makeCall(op, e)); - - /* Try to find the dependencies relative to the `path'. */ - for (ATermIterator i(res); i; ++i) - workSet.insert(evalExpr(state, *i)); + Value call; + mkApp(call, op->second.value, *e); + state.forceList(call); + + /* Add the values returned by the operator to the work set. */ + for (unsigned int n = 0; n < call.list.length; ++n) { + state.forceValue(*call.list.elems[n]); + workSet.push_back(call.list.elems[n]); + } } - return makeList(res); + /* Create the result list. */ + state.mkList(v, res.size()); + Value * vs = state.allocValues(res.size()); + + unsigned int n = 0; + foreach (list<Value>::iterator, i, res) { + v.list.elems[n] = &vs[n]; + vs[n++] = *i; + } } -static Expr prim_abort(EvalState & state, const ATermVector & args) +static void prim_abort(EvalState & state, Value * * args, Value & v) { PathSet context; throw Abort(format("evaluation aborted with the following error message: `%1%'") % - evalString(state, args[0], context)); + state.coerceToString(*args[0], context)); } -static Expr prim_throw(EvalState & state, const ATermVector & args) +static void prim_throw(EvalState & state, Value * * args, Value & v) { PathSet context; throw ThrownError(format("user-thrown exception: %1%") % - evalString(state, args[0], context)); + state.coerceToString(*args[0], context)); } -static Expr prim_addErrorContext(EvalState & state, const ATermVector & args) +static void prim_addErrorContext(EvalState & state, Value * * args, Value & v) { - PathSet context; try { - return evalExpr(state, args[1]); + state.forceValue(*args[1]); + v = *args[1]; } catch (Error & e) { - e.addPrefix(format("%1%\n") % - evalString(state, args[0], context)); + PathSet context; + e.addPrefix(format("%1%\n") % state.coerceToString(*args[0], context)); throw; } } + +#if 0 /* Try evaluating the argument. Success => {success=true; value=something;}, * else => {success=false; value=false;} */ -static Expr prim_tryEval(EvalState & state, const ATermVector & args) +static void prim_tryEval(EvalState & state, Value * * args, Value & v) { ATermMap res = ATermMap(); try { @@ -239,30 +219,28 @@ static Expr prim_tryEval(EvalState & state, const ATermVector & args) } return makeAttrs(res); } +#endif /* Return an environment variable. Use with care. */ -static Expr prim_getEnv(EvalState & state, const ATermVector & args) +static void prim_getEnv(EvalState & state, Value * * args, Value & v) { - string name = evalStringNoCtx(state, args[0]); - return makeStr(getEnv(name)); + string name = state.forceStringNoCtx(*args[0]); + mkString(v, getEnv(name)); } -/* Evaluate the first expression, and print its abstract syntax tree - on standard error. Then return the second expression. Useful for - debugging. - */ -static Expr prim_trace(EvalState & state, const ATermVector & args) +/* Evaluate the first expression and print it on standard error. Then + return the second expression. Useful for debugging. */ +static void prim_trace(EvalState & state, Value * * args, Value & v) { - Expr e = evalExpr(state, args[0]); - string s; - PathSet context; - if (matchStr(e, s, context)) - printMsg(lvlError, format("trace: %1%") % s); + state.forceValue(*args[0]); + if (args[0]->type == tString) + printMsg(lvlError, format("trace: %1%") % args[0]->string.s); else - printMsg(lvlError, format("trace: %1%") % e); - return evalExpr(state, args[1]); + printMsg(lvlError, format("trace: %1%") % *args[0]); + state.forceValue(*args[1]); + v = *args[1]; } @@ -324,7 +302,7 @@ static Hash hashDerivationModulo(EvalState & state, Derivation drv) } drv.inputDrvs = inputs2; - return hashTerm(unparseDerivation(drv)); + return hashString(htSHA256, unparseDerivation(drv)); } @@ -335,28 +313,25 @@ static Hash hashDerivationModulo(EvalState & state, Derivation drv) derivation; `drvPath' containing the path of the Nix expression; and `type' set to `derivation' to indicate that this is a derivation. */ -static Expr prim_derivationStrict(EvalState & state, const ATermVector & args) +static void prim_derivationStrict(EvalState & state, Value * * args, Value & v) { startNest(nest, lvlVomit, "evaluating derivation"); - ATermMap attrs; - queryAllAttrs(evalExpr(state, args[0]), attrs, true); + state.forceAttrs(*args[0]); - /* Figure out the name already (for stack backtraces). */ - ATerm posDrvName; - Expr eDrvName = attrs.get(toATerm("name")); - if (!eDrvName) + /* Figure out the name first (for stack backtraces). */ + Bindings::iterator attr = args[0]->attrs->find(state.sName); + if (attr == args[0]->attrs->end()) throw EvalError("required attribute `name' missing"); - if (!matchAttrRHS(eDrvName, eDrvName, posDrvName)) abort(); string drvName; + Pos & posDrvName(*attr->second.pos); try { - drvName = evalStringNoCtx(state, eDrvName); + drvName = state.forceStringNoCtx(attr->second.value); } catch (Error & e) { - e.addPrefix(format("while evaluating the derivation attribute `name' at %1%:\n") - % showPos(posDrvName)); + e.addPrefix(format("while evaluating the derivation attribute `name' at %1%:\n") % posDrvName); throw; } - + /* Build the derivation expression by processing the attributes. */ Derivation drv; @@ -365,12 +340,8 @@ static Expr prim_derivationStrict(EvalState & state, const ATermVector & args) string outputHash, outputHashAlgo; bool outputHashRecursive = false; - for (ATermMap::const_iterator i = attrs.begin(); i != attrs.end(); ++i) { - string key = aterm2String(i->key); - ATerm value; - Expr pos; - ATerm rhs = i->value; - if (!matchAttrRHS(rhs, value, pos)) abort(); + foreach (Bindings::iterator, i, *args[0]->attrs) { + string key = i->first; startNest(nest, lvlVomit, format("processing attribute `%1%'") % key); try { @@ -378,15 +349,9 @@ static Expr prim_derivationStrict(EvalState & state, const ATermVector & args) /* The `args' attribute is special: it supplies the command-line arguments to the builder. */ if (key == "args") { - ATermList es; - value = evalExpr(state, value); - if (!matchList(value, es)) { - static bool haveWarned = false; - warnOnce(haveWarned, "the `args' attribute should evaluate to a list"); - es = flattenList(state, value); - } - for (ATermIterator i(es); i; ++i) { - string s = coerceToString(state, *i, context, true); + state.forceList(i->second.value); + for (unsigned int n = 0; n < i->second.value.list.length; ++n) { + string s = state.coerceToString(*i->second.value.list.elems[n], context, true); drv.args.push_back(s); } } @@ -394,11 +359,11 @@ static Expr prim_derivationStrict(EvalState & state, const ATermVector & args) /* All other attributes are passed to the builder through the environment. */ else { - string s = coerceToString(state, value, context, true); + string s = state.coerceToString(i->second.value, context, true); drv.env[key] = s; if (key == "builder") drv.builder = s; - else if (key == "system") drv.platform = s; - else if (key == "name") drvName = s; + else if (i->first == state.sSystem) drv.platform = s; + else if (i->first == state.sName) drvName = s; else if (key == "outputHash") outputHash = s; else if (key == "outputHashAlgo") outputHashAlgo = s; else if (key == "outputHashMode") { @@ -410,12 +375,11 @@ static Expr prim_derivationStrict(EvalState & state, const ATermVector & args) } catch (Error & e) { e.addPrefix(format("while evaluating the derivation attribute `%1%' at %2%:\n") - % key % showPos(pos)); + % key % *i->second.pos); e.addPrefix(format("while instantiating the derivation named `%1%' at %2%:\n") - % drvName % showPos(posDrvName)); + % drvName % posDrvName); throw; } - } /* Everything in the context of the strings in the derivation @@ -523,33 +487,9 @@ static Expr prim_derivationStrict(EvalState & state, const ATermVector & args) state.drvHashes[drvPath] = hashDerivationModulo(state, drv); /* !!! assumes a single output */ - ATermMap outAttrs(2); - outAttrs.set(toATerm("outPath"), - makeAttrRHS(makeStr(outPath, singleton<PathSet>(drvPath)), makeNoPos())); - outAttrs.set(toATerm("drvPath"), - makeAttrRHS(makeStr(drvPath, singleton<PathSet>("=" + drvPath)), makeNoPos())); - - return makeAttrs(outAttrs); -} - - -static Expr prim_derivationLazy(EvalState & state, const ATermVector & args) -{ - Expr eAttrs = evalExpr(state, args[0]); - ATermMap attrs; - queryAllAttrs(eAttrs, attrs, true); - - attrs.set(toATerm("type"), - makeAttrRHS(makeStr("derivation"), makeNoPos())); - - Expr drvStrict = makeCall(makeVar(toATerm("derivation!")), eAttrs); - - attrs.set(toATerm("outPath"), - makeAttrRHS(makeSelect(drvStrict, toATerm("outPath")), makeNoPos())); - attrs.set(toATerm("drvPath"), - makeAttrRHS(makeSelect(drvStrict, toATerm("drvPath")), makeNoPos())); - - return makeAttrs(attrs); + state.mkAttrs(v); + mkString((*v.attrs)[state.sOutPath].value, outPath, singleton<PathSet>(drvPath)); + mkString((*v.attrs)[state.sDrvPath].value, drvPath, singleton<PathSet>("=" + drvPath)); } @@ -559,11 +499,11 @@ static Expr prim_derivationLazy(EvalState & state, const ATermVector & args) /* Convert the argument to a path. !!! obsolete? */ -static Expr prim_toPath(EvalState & state, const ATermVector & args) +static void prim_toPath(EvalState & state, Value * * args, Value & v) { PathSet context; - string path = coerceToPath(state, args[0], context); - return makeStr(canonPath(path), context); + Path path = state.coerceToPath(*args[0], context); + mkString(v, canonPath(path), context); } @@ -575,60 +515,58 @@ static Expr prim_toPath(EvalState & state, const ATermVector & args) /nix/store/newhash-oldhash-oldname. In the past, `toPath' had special case behaviour for store paths, but that created weird corner cases. */ -static Expr prim_storePath(EvalState & state, const ATermVector & args) +static void prim_storePath(EvalState & state, Value * * args, Value & v) { PathSet context; - Path path = canonPath(coerceToPath(state, args[0], context)); + Path path = canonPath(state.coerceToPath(*args[0], context)); if (!isInStore(path)) throw EvalError(format("path `%1%' is not in the Nix store") % path); Path path2 = toStorePath(path); if (!store->isValidPath(path2)) throw EvalError(format("store path `%1%' is not valid") % path2); context.insert(path2); - return makeStr(path, context); + mkString(v, path, context); } -static Expr prim_pathExists(EvalState & state, const ATermVector & args) +static void prim_pathExists(EvalState & state, Value * * args, Value & v) { PathSet context; - Path path = coerceToPath(state, args[0], context); + Path path = state.coerceToPath(*args[0], context); if (!context.empty()) throw EvalError(format("string `%1%' cannot refer to other paths") % path); - return makeBool(pathExists(path)); + mkBool(v, pathExists(path)); } /* Return the base name of the given string, i.e., everything following the last slash. */ -static Expr prim_baseNameOf(EvalState & state, const ATermVector & args) +static void prim_baseNameOf(EvalState & state, Value * * args, Value & v) { PathSet context; - return makeStr(baseNameOf(coerceToString(state, args[0], context)), context); + mkString(v, baseNameOf(state.coerceToString(*args[0], context)), context); } /* Return the directory of the given path, i.e., everything before the last slash. Return either a path or a string depending on the type of the argument. */ -static Expr prim_dirOf(EvalState & state, const ATermVector & args) +static void prim_dirOf(EvalState & state, Value * * args, Value & v) { PathSet context; - Expr e = evalExpr(state, args[0]); ATerm dummy; - bool isPath = matchPath(e, dummy); - Path dir = dirOf(coerceToPath(state, e, context)); - return isPath ? makePath(toATerm(dir)) : makeStr(dir, context); + Path dir = dirOf(state.coerceToPath(*args[0], context)); + if (args[0]->type == tPath) mkPath(v, dir.c_str()); else mkString(v, dir, context); } /* Return the contents of a file as a string. */ -static Expr prim_readFile(EvalState & state, const ATermVector & args) +static void prim_readFile(EvalState & state, Value * * args, Value & v) { PathSet context; - Path path = coerceToPath(state, args[0], context); + Path path = state.coerceToPath(*args[0], context); if (!context.empty()) throw EvalError(format("string `%1%' cannot refer to other paths") % path); - return makeStr(readFile(path)); + mkString(v, readFile(path).c_str()); } @@ -640,26 +578,26 @@ static Expr prim_readFile(EvalState & state, const ATermVector & args) /* Convert the argument (which can be any Nix expression) to an XML representation returned in a string. Not all Nix expressions can be sensibly or completely represented (e.g., functions). */ -static Expr prim_toXML(EvalState & state, const ATermVector & args) +static void prim_toXML(EvalState & state, Value * * args, Value & v) { std::ostringstream out; PathSet context; - printTermAsXML(strictEvalExpr(state, args[0]), out, context); - return makeStr(out.str(), context); + printValueAsXML(state, true, false, *args[0], out, context); + mkString(v, out.str(), context); } /* Store a string in the Nix store as a source file that can be used as an input by derivations. */ -static Expr prim_toFile(EvalState & state, const ATermVector & args) +static void prim_toFile(EvalState & state, Value * * args, Value & v) { PathSet context; - string name = evalStringNoCtx(state, args[0]); - string contents = evalString(state, args[1], context); + string name = state.forceStringNoCtx(*args[0]); + string contents = state.forceString(*args[1], context); PathSet refs; - for (PathSet::iterator i = context.begin(); i != context.end(); ++i) { + foreach (PathSet::iterator, i, context) { Path path = *i; if (path.at(0) == '=') path = string(path, 1); if (isDerivation(path)) @@ -674,17 +612,17 @@ static Expr prim_toFile(EvalState & state, const ATermVector & args) /* Note: we don't need to add `context' to the context of the result, since `storePath' itself has references to the paths used in args[1]. */ - - return makeStr(storePath, singleton<PathSet>(storePath)); + + mkString(v, storePath, singleton<PathSet>(storePath)); } struct FilterFromExpr : PathFilter { EvalState & state; - Expr filter; + Value & filter; - FilterFromExpr(EvalState & state, Expr filter) + FilterFromExpr(EvalState & state, Value & filter) : state(state), filter(filter) { } @@ -695,35 +633,47 @@ struct FilterFromExpr : PathFilter if (lstat(path.c_str(), &st)) throw SysError(format("getting attributes of path `%1%'") % path); - Expr call = - makeCall( - makeCall(filter, makeStr(path)), - makeStr( - S_ISREG(st.st_mode) ? "regular" : - S_ISDIR(st.st_mode) ? "directory" : - S_ISLNK(st.st_mode) ? "symlink" : - "unknown" /* not supported, will fail! */ - )); - - return evalBool(state, call); + /* Call the filter function. The first argument is the path, + the second is a string indicating the type of the file. */ + Value arg1; + mkString(arg1, path); + + Value fun2; + state.callFunction(filter, arg1, fun2); + + Value arg2; + mkString(arg2, + S_ISREG(st.st_mode) ? "regular" : + S_ISDIR(st.st_mode) ? "directory" : + S_ISLNK(st.st_mode) ? "symlink" : + "unknown" /* not supported, will fail! */); + + Value res; + state.callFunction(fun2, arg2, res); + + return state.forceBool(res); } }; -static Expr prim_filterSource(EvalState & state, const ATermVector & args) +static void prim_filterSource(EvalState & state, Value * * args, Value & v) { PathSet context; - Path path = coerceToPath(state, args[1], context); + Path path = state.coerceToPath(*args[1], context); if (!context.empty()) throw EvalError(format("string `%1%' cannot refer to other paths") % path); - FilterFromExpr filter(state, args[0]); + state.forceValue(*args[0]); + if (args[0]->type != tLambda) + throw TypeError(format("first argument in call to `filterSource' is not a function but %1%") % showType(*args[0])); + + FilterFromExpr filter(state, *args[0]); Path dstPath = readOnlyMode ? computeStorePathForPath(path, true, htSHA256, filter).first : store->addToStore(path, true, htSHA256, filter); - return makeStr(dstPath, singleton<PathSet>(dstPath)); + mkString(v, dstPath, singleton<PathSet>(dstPath)); } @@ -734,131 +684,119 @@ static Expr prim_filterSource(EvalState & state, const ATermVector & args) /* Return the names of the attributes in an attribute set as a sorted list of strings. */ -static Expr prim_attrNames(EvalState & state, const ATermVector & args) +static void prim_attrNames(EvalState & state, Value * * args, Value & v) { - ATermMap attrs; - queryAllAttrs(evalExpr(state, args[0]), attrs); + state.forceAttrs(*args[0]); - StringSet names; - for (ATermMap::const_iterator i = attrs.begin(); i != attrs.end(); ++i) - names.insert(aterm2String(i->key)); + state.mkList(v, args[0]->attrs->size()); + Value * vs = state.allocValues(v.list.length); - ATermList list = ATempty; - for (StringSet::const_reverse_iterator i = names.rbegin(); - i != names.rend(); ++i) - list = ATinsert(list, makeStr(*i, PathSet())); + StringSet names; + foreach (Bindings::iterator, i, *args[0]->attrs) + names.insert(i->first); - return makeList(list); + unsigned int n = 0; + foreach (StringSet::iterator, i, names) { + v.list.elems[n] = &vs[n]; + mkString(vs[n++], *i); + } } /* Dynamic version of the `.' operator. */ -static Expr prim_getAttr(EvalState & state, const ATermVector & args) +static void prim_getAttr(EvalState & state, Value * * args, Value & v) { - string attr = evalStringNoCtx(state, args[0]); - return evalExpr(state, makeSelect(args[1], toATerm(attr))); + string attr = state.forceStringNoCtx(*args[0]); + state.forceAttrs(*args[1]); + // !!! Should we create a symbol here or just do a lookup? + Bindings::iterator i = args[1]->attrs->find(state.symbols.create(attr)); + if (i == args[1]->attrs->end()) + throw EvalError(format("attribute `%1%' missing") % attr); + // !!! add to stack trace? + state.forceValue(i->second.value); + v = i->second.value; } /* Dynamic version of the `?' operator. */ -static Expr prim_hasAttr(EvalState & state, const ATermVector & args) +static void prim_hasAttr(EvalState & state, Value * * args, Value & v) { - string attr = evalStringNoCtx(state, args[0]); - return evalExpr(state, makeOpHasAttr(args[1], toATerm(attr))); + string attr = state.forceStringNoCtx(*args[0]); + state.forceAttrs(*args[1]); + mkBool(v, args[1]->attrs->find(state.symbols.create(attr)) != args[1]->attrs->end()); } -/* Builds an attribute set from a list specifying (name, value) - pairs. To be precise, a list [{name = "name1"; value = value1;} - ... {name = "nameN"; value = valueN;}] is transformed to {name1 = - value1; ... nameN = valueN;}. */ -static Expr prim_listToAttrs(EvalState & state, const ATermVector & args) +/* Determine whether the argument is an attribute set. */ +static void prim_isAttrs(EvalState & state, Value * * args, Value & v) { - try { - ATermMap res = ATermMap(); - ATermList list; - list = evalList(state, args[0]); - for (ATermIterator i(list); i; ++i){ - // *i should now contain a pointer to the list item expression - ATermList attrs; - Expr evaledExpr = evalExpr(state, *i); - if (matchAttrs(evaledExpr, attrs)){ - Expr e = evalExpr(state, makeSelect(evaledExpr, toATerm("name"))); - string attr = evalStringNoCtx(state,e); - Expr r = makeSelect(evaledExpr, toATerm("value")); - res.set(toATerm(attr), makeAttrRHS(r, makeNoPos())); - } - else - throw TypeError(format("list element in `listToAttrs' is %s, expected a set { name = \"<name>\"; value = <value>; }") - % showType(evaledExpr)); - } - - return makeAttrs(res); - - } catch (Error & e) { - e.addPrefix(format("in `listToAttrs':\n")); - throw; - } + state.forceValue(*args[0]); + mkBool(v, args[0]->type == tAttrs); } -static Expr prim_removeAttrs(EvalState & state, const ATermVector & args) +static void prim_removeAttrs(EvalState & state, Value * * args, Value & v) { - ATermMap attrs; - queryAllAttrs(evalExpr(state, args[0]), attrs, true); - - ATermList list = evalList(state, args[1]); + state.forceAttrs(*args[0]); + state.forceList(*args[1]); - for (ATermIterator i(list); i; ++i) - /* It's not an error for *i not to exist. */ - attrs.remove(toATerm(evalStringNoCtx(state, *i))); + state.cloneAttrs(*args[0], v); - return makeAttrs(attrs); + for (unsigned int i = 0; i < args[1]->list.length; ++i) { + state.forceStringNoCtx(*args[1]->list.elems[i]); + v.attrs->erase(state.symbols.create(args[1]->list.elems[i]->string.s)); + } } -/* Determine whether the argument is an attribute set. */ -static Expr prim_isAttrs(EvalState & state, const ATermVector & args) +/* Builds an attribute set from a list specifying (name, value) + pairs. To be precise, a list [{name = "name1"; value = value1;} + ... {name = "nameN"; value = valueN;}] is transformed to {name1 = + value1; ... nameN = valueN;}. */ +static void prim_listToAttrs(EvalState & state, Value * * args, Value & v) { - ATermList list; - return makeBool(matchAttrs(evalExpr(state, args[0]), list)); -} - + state.forceList(*args[0]); -/* Return the right-biased intersection of two attribute sets as1 and - as2, i.e. a set that contains every attribute from as2 that is also - a member of as1. */ -static Expr prim_intersectAttrs(EvalState & state, const ATermVector & args) -{ - ATermMap as1, as2; - queryAllAttrs(evalExpr(state, args[0]), as1, true); - queryAllAttrs(evalExpr(state, args[1]), as2, true); + state.mkAttrs(v); - ATermMap res; - foreach (ATermMap::const_iterator, i, as2) - if (as1[i->key]) res.set(i->key, i->value); + for (unsigned int i = 0; i < args[0]->list.length; ++i) { + Value & v2(*args[0]->list.elems[i]); + state.forceAttrs(v2); + + Bindings::iterator j = v2.attrs->find(state.sName); + if (j == v2.attrs->end()) + throw TypeError("`name' attribute missing in a call to `listToAttrs'"); + string name = state.forceStringNoCtx(j->second.value); + + j = v2.attrs->find(state.symbols.create("value")); + if (j == v2.attrs->end()) + throw TypeError("`value' attribute missing in a call to `listToAttrs'"); - return makeAttrs(res); + Attr & a = (*v.attrs)[state.symbols.create(name)]; + mkCopy(a.value, j->second.value); + a.pos = j->second.pos; + } } -static void attrsInPattern(ATermMap & map, Pattern pat) +/* Return the right-biased intersection of two attribute sets as1 and + as2, i.e. a set that contains every attribute from as2 that is also + a member of as1. */ +static void prim_intersectAttrs(EvalState & state, Value * * args, Value & v) { - ATerm name; - ATermList formals; - Pattern pat1, pat2; - ATermBool ellipsis; - if (matchAttrsPat(pat, formals, ellipsis)) { - for (ATermIterator i(formals); i; ++i) { - ATerm def; - if (!matchFormal(*i, name, def)) abort(); - map.set(name, makeAttrRHS(makeBool(def != constNoDefaultValue), makeNoPos())); + state.forceAttrs(*args[0]); + state.forceAttrs(*args[1]); + + state.mkAttrs(v); + + foreach (Bindings::iterator, i, *args[1]->attrs) { + Bindings::iterator j = args[0]->attrs->find(i->first); + if (j != args[0]->attrs->end()) { + Attr & a = (*v.attrs)[i->first]; + mkCopy(a.value, i->second.value); + a.pos = i->second.pos; } } - else if (matchAtPat(pat, pat1, pat2)) { - attrsInPattern(map, pat1); - attrsInPattern(map, pat2); - } } @@ -875,17 +813,18 @@ static void attrsInPattern(ATermMap & map, Pattern pat) functionArgs (x: ...) => { } */ -static Expr prim_functionArgs(EvalState & state, const ATermVector & args) +static void prim_functionArgs(EvalState & state, Value * * args, Value & v) { - Expr f = evalExpr(state, args[0]); - ATerm pat, body, pos; - if (!matchFunction(f, pat, body, pos)) - throw TypeError("`functionArgs' required a function"); - - ATermMap as; - attrsInPattern(as, pat); + state.forceValue(*args[0]); + if (args[0]->type != tLambda) + throw TypeError("`functionArgs' requires a function"); - return makeAttrs(as); + state.mkAttrs(v); + + if (!args[0]->lambda.fun->matchAttrs) return; + + foreach (Formals::Formals_::iterator, i, args[0]->lambda.fun->formals->formals) + mkBool((*v.attrs)[i->name].value, i->def); } @@ -895,53 +834,58 @@ static Expr prim_functionArgs(EvalState & state, const ATermVector & args) /* Determine whether the argument is a list. */ -static Expr prim_isList(EvalState & state, const ATermVector & args) +static void prim_isList(EvalState & state, Value * * args, Value & v) { - ATermList list; - return makeBool(matchList(evalExpr(state, args[0]), list)); + state.forceValue(*args[0]); + mkBool(v, args[0]->type == tList); } /* Return the first element of a list. */ -static Expr prim_head(EvalState & state, const ATermVector & args) +static void prim_head(EvalState & state, Value * * args, Value & v) { - ATermList list = evalList(state, args[0]); - if (ATisEmpty(list)) + state.forceList(*args[0]); + if (args[0]->list.length == 0) throw Error("`head' called on an empty list"); - return evalExpr(state, ATgetFirst(list)); + state.forceValue(*args[0]->list.elems[0]); + v = *args[0]->list.elems[0]; } /* Return a list consisting of everything but the the first element of a list. */ -static Expr prim_tail(EvalState & state, const ATermVector & args) +static void prim_tail(EvalState & state, Value * * args, Value & v) { - ATermList list = evalList(state, args[0]); - if (ATisEmpty(list)) + state.forceList(*args[0]); + if (args[0]->list.length == 0) throw Error("`tail' called on an empty list"); - return makeList(ATgetNext(list)); + state.mkList(v, args[0]->list.length - 1); + for (unsigned int n = 0; n < v.list.length; ++n) + v.list.elems[n] = args[0]->list.elems[n + 1]; } /* Apply a function to every element of a list. */ -static Expr prim_map(EvalState & state, const ATermVector & args) +static void prim_map(EvalState & state, Value * * args, Value & v) { - Expr fun = evalExpr(state, args[0]); - ATermList list = evalList(state, args[1]); + state.forceFunction(*args[0]); + state.forceList(*args[1]); - ATermList res = ATempty; - for (ATermIterator i(list); i; ++i) - res = ATinsert(res, makeCall(fun, *i)); + state.mkList(v, args[1]->list.length); + Value * vs = state.allocValues(v.list.length); - return makeList(ATreverse(res)); + for (unsigned int n = 0; n < v.list.length; ++n) { + v.list.elems[n] = &vs[n]; + mkApp(vs[n], *args[0], *args[1]->list.elems[n]); + } } /* Return the length of a list. This is an O(1) time operation. */ -static Expr prim_length(EvalState & state, const ATermVector & args) +static void prim_length(EvalState & state, Value * * args, Value & v) { - ATermList list = evalList(state, args[0]); - return makeInt(ATgetLength(list)); + state.forceList(*args[0]); + mkInt(v, args[0]->list.length); } @@ -950,44 +894,35 @@ static Expr prim_length(EvalState & state, const ATermVector & args) *************************************************************/ -static Expr prim_add(EvalState & state, const ATermVector & args) +static void prim_add(EvalState & state, Value * * args, Value & v) { - int i1 = evalInt(state, args[0]); - int i2 = evalInt(state, args[1]); - return makeInt(i1 + i2); + mkInt(v, state.forceInt(*args[0]) + state.forceInt(*args[1])); } -static Expr prim_sub(EvalState & state, const ATermVector & args) +static void prim_sub(EvalState & state, Value * * args, Value & v) { - int i1 = evalInt(state, args[0]); - int i2 = evalInt(state, args[1]); - return makeInt(i1 - i2); + mkInt(v, state.forceInt(*args[0]) - state.forceInt(*args[1])); } -static Expr prim_mul(EvalState & state, const ATermVector & args) +static void prim_mul(EvalState & state, Value * * args, Value & v) { - int i1 = evalInt(state, args[0]); - int i2 = evalInt(state, args[1]); - return makeInt(i1 * i2); + mkInt(v, state.forceInt(*args[0]) * state.forceInt(*args[1])); } -static Expr prim_div(EvalState & state, const ATermVector & args) +static void prim_div(EvalState & state, Value * * args, Value & v) { - int i1 = evalInt(state, args[0]); - int i2 = evalInt(state, args[1]); + int i2 = state.forceInt(*args[1]); if (i2 == 0) throw EvalError("division by zero"); - return makeInt(i1 / i2); + mkInt(v, state.forceInt(*args[0]) / i2); } -static Expr prim_lessThan(EvalState & state, const ATermVector & args) +static void prim_lessThan(EvalState & state, Value * * args, Value & v) { - int i1 = evalInt(state, args[0]); - int i2 = evalInt(state, args[1]); - return makeBool(i1 < i2); + mkBool(v, state.forceInt(*args[0]) < state.forceInt(*args[1])); } @@ -999,11 +934,11 @@ static Expr prim_lessThan(EvalState & state, const ATermVector & args) /* Convert the argument to a string. Paths are *not* copied to the store, so `toString /foo/bar' yields `"/foo/bar"', not `"/nix/store/whatever..."'. */ -static Expr prim_toString(EvalState & state, const ATermVector & args) +static void prim_toString(EvalState & state, Value * * args, Value & v) { PathSet context; - string s = coerceToString(state, args[0], context, true, false); - return makeStr(s, context); + string s = state.coerceToString(*args[0], context, true, false); + mkString(v, s, context); } @@ -1011,32 +946,32 @@ static Expr prim_toString(EvalState & state, const ATermVector & args) at character position `min(start, stringLength str)' inclusive and ending at `min(start + len, stringLength str)'. `start' must be non-negative. */ -static Expr prim_substring(EvalState & state, const ATermVector & args) +static void prim_substring(EvalState & state, Value * * args, Value & v) { - int start = evalInt(state, args[0]); - int len = evalInt(state, args[1]); + int start = state.forceInt(*args[0]); + int len = state.forceInt(*args[1]); PathSet context; - string s = coerceToString(state, args[2], context); + string s = state.coerceToString(*args[2], context); if (start < 0) throw EvalError("negative start position in `substring'"); - return makeStr(string(s, start, len), context); + mkString(v, string(s, start, len), context); } -static Expr prim_stringLength(EvalState & state, const ATermVector & args) +static void prim_stringLength(EvalState & state, Value * * args, Value & v) { PathSet context; - string s = coerceToString(state, args[0], context); - return makeInt(s.size()); + string s = state.coerceToString(*args[0], context); + mkInt(v, s.size()); } -static Expr prim_unsafeDiscardStringContext(EvalState & state, const ATermVector & args) +static void prim_unsafeDiscardStringContext(EvalState & state, Value * * args, Value & v) { PathSet context; - string s = coerceToString(state, args[0], context); - return makeStr(s, PathSet()); + string s = state.coerceToString(*args[0], context); + mkString(v, s, PathSet()); } @@ -1046,10 +981,10 @@ static Expr prim_unsafeDiscardStringContext(EvalState & state, const ATermVector source-only deployment). This primop marks the string context so that builtins.derivation adds the path to drv.inputSrcs rather than drv.inputDrvs. */ -static Expr prim_unsafeDiscardOutputDependency(EvalState & state, const ATermVector & args) +static void prim_unsafeDiscardOutputDependency(EvalState & state, Value * * args, Value & v) { PathSet context; - string s = coerceToString(state, args[0], context); + string s = state.coerceToString(*args[0], context); PathSet context2; foreach (PathSet::iterator, i, context) { @@ -1058,29 +993,7 @@ static Expr prim_unsafeDiscardOutputDependency(EvalState & state, const ATermVec context2.insert(p); } - return makeStr(s, context2); -} - - -/* Expression serialization/deserialization */ - - -static Expr prim_exprToString(EvalState & state, const ATermVector & args) -{ - /* !!! this disregards context */ - return makeStr(atPrint(evalExpr(state, args[0]))); -} - - -static Expr prim_stringToExpr(EvalState & state, const ATermVector & args) -{ - /* !!! this can introduce arbitrary garbage terms in the - evaluator! */; - string s; - PathSet l; - if (!matchStr(evalExpr(state, args[0]), s, l)) - throw EvalError("stringToExpr needs string argument!"); - return ATreadFromString(s.c_str()); + mkString(v, s, context2); } @@ -1089,23 +1002,21 @@ static Expr prim_stringToExpr(EvalState & state, const ATermVector & args) *************************************************************/ -static Expr prim_parseDrvName(EvalState & state, const ATermVector & args) +static void prim_parseDrvName(EvalState & state, Value * * args, Value & v) { - string name = evalStringNoCtx(state, args[0]); + string name = state.forceStringNoCtx(*args[0]); DrvName parsed(name); - ATermMap attrs(2); - attrs.set(toATerm("name"), makeAttrRHS(makeStr(parsed.name), makeNoPos())); - attrs.set(toATerm("version"), makeAttrRHS(makeStr(parsed.version), makeNoPos())); - return makeAttrs(attrs); + state.mkAttrs(v); + mkString((*v.attrs)[state.sName].value, parsed.name); + mkString((*v.attrs)[state.symbols.create("version")].value, parsed.version); } -static Expr prim_compareVersions(EvalState & state, const ATermVector & args) +static void prim_compareVersions(EvalState & state, Value * * args, Value & v) { - string version1 = evalStringNoCtx(state, args[0]); - string version2 = evalStringNoCtx(state, args[1]); - int d = compareVersions(version1, version2); - return makeInt(d); + string version1 = state.forceStringNoCtx(*args[0]); + string version2 = state.forceStringNoCtx(*args[1]); + mkInt(v, compareVersions(version1, version2)); } @@ -1114,16 +1025,31 @@ static Expr prim_compareVersions(EvalState & state, const ATermVector & args) *************************************************************/ -void EvalState::addPrimOps() +void EvalState::createBaseEnv() { - addPrimOp("builtins", 0, prim_builtins); - - // Constants - addPrimOp("true", 0, prim_true); - addPrimOp("false", 0, prim_false); - addPrimOp("null", 0, prim_null); - addPrimOp("__currentSystem", 0, prim_currentSystem); - addPrimOp("__currentTime", 0, prim_currentTime); + baseEnv.up = 0; + + /* Add global constants such as `true' to the base environment. */ + Value v; + + /* `builtins' must be first! */ + mkAttrs(v); + addConstant("builtins", v); + + mkBool(v, true); + addConstant("true", v); + + mkBool(v, false); + addConstant("false", v); + + v.type = tNull; + addConstant("null", v); + + mkInt(v, time(0)); + addConstant("__currentTime", v); + + mkString(v, thisSystem.c_str()); + addConstant("__currentSystem", v); // Miscellaneous addPrimOp("import", 1, prim_import); @@ -1136,18 +1062,20 @@ void EvalState::addPrimOps() addPrimOp("abort", 1, prim_abort); addPrimOp("throw", 1, prim_throw); addPrimOp("__addErrorContext", 2, prim_addErrorContext); +#if 0 addPrimOp("__tryEval", 1, prim_tryEval); +#endif addPrimOp("__getEnv", 1, prim_getEnv); addPrimOp("__trace", 2, prim_trace); - - // Expr <-> String - addPrimOp("__exprToString", 1, prim_exprToString); - addPrimOp("__stringToExpr", 1, prim_stringToExpr); - // Derivations - addPrimOp("derivation!", 1, prim_derivationStrict); - addPrimOp("derivation", 1, prim_derivationLazy); + addPrimOp("derivationStrict", 1, prim_derivationStrict); + + /* Add a wrapper around the derivation primop that computes the + `drvPath' and `outPath' attributes lazily. */ + string s = "attrs: let res = derivationStrict attrs; in attrs // { drvPath = res.drvPath; outPath = res.outPath; type = \"derivation\"; }"; + mkThunk(v, baseEnv, parseExprFromString(*this, s, "/")); + addConstant("derivation", v); // Paths addPrimOp("__toPath", 1, prim_toPath); @@ -1178,7 +1106,7 @@ void EvalState::addPrimOps() addPrimOp("__tail", 1, prim_tail); addPrimOp("map", 2, prim_map); addPrimOp("__length", 1, prim_length); - + // Integer arithmetic addPrimOp("__add", 2, prim_add); addPrimOp("__sub", 2, prim_sub); @@ -1195,7 +1123,7 @@ void EvalState::addPrimOps() // Versions addPrimOp("__parseDrvName", 1, prim_parseDrvName); - addPrimOp("__compareVersions", 2, prim_compareVersions); + addPrimOp("__compareVersions", 2, prim_compareVersions); } diff --git a/src/libexpr/symbol-table.hh b/src/libexpr/symbol-table.hh new file mode 100644 index 0000000000..424c235389 --- /dev/null +++ b/src/libexpr/symbol-table.hh @@ -0,0 +1,81 @@ +#ifndef __SYMBOL_TABLE_H +#define __SYMBOL_TABLE_H + +#include <map> +#include <tr1/unordered_set> + +#include "types.hh" + +namespace nix { + +/* Symbol table used by the parser and evaluator to represent and look + up identifiers and attribute sets efficiently. + SymbolTable::create() converts a string into a symbol. Symbols + have the property that they can be compared efficiently (using a + pointer equality test), because the symbol table stores only one + copy of each string. */ + +class Symbol +{ +private: + const string * s; // pointer into SymbolTable + Symbol(const string * s) : s(s) { }; + friend class SymbolTable; + +public: + bool operator == (const Symbol & s2) const + { + return s == s2.s; + } + + bool operator != (const Symbol & s2) const + { + return s != s2.s; + } + + bool operator < (const Symbol & s2) const + { + return s < s2.s; + } + + operator const string & () const + { + return *s; + } + + bool empty() const + { + return s->empty(); + } + + friend std::ostream & operator << (std::ostream & str, const Symbol & sym); +}; + +inline std::ostream & operator << (std::ostream & str, const Symbol & sym) +{ + str << *sym.s; + return str; +} + +class SymbolTable +{ +private: + typedef std::tr1::unordered_set<string> Symbols; + Symbols symbols; + +public: + Symbol create(const string & s) + { + std::pair<Symbols::iterator, bool> res = symbols.insert(s); + return Symbol(&*res.first); + } + + unsigned int size() const + { + return symbols.size(); + } +}; + +} + +#endif /* !__SYMBOL_TABLE_H */ diff --git a/src/libexpr/value-to-xml.cc b/src/libexpr/value-to-xml.cc new file mode 100644 index 0000000000..c3f352cfbd --- /dev/null +++ b/src/libexpr/value-to-xml.cc @@ -0,0 +1,159 @@ +#include "value-to-xml.hh" +#include "xml-writer.hh" +#include "util.hh" + +#include <cstdlib> + + +namespace nix { + + +static XMLAttrs singletonAttrs(const string & name, const string & value) +{ + XMLAttrs attrs; + attrs[name] = value; + return attrs; +} + + +static void printValueAsXML(EvalState & state, bool strict, bool location, + Value & v, XMLWriter & doc, PathSet & context, PathSet & drvsSeen); + + +static void posToXML(XMLAttrs & xmlAttrs, const Pos & pos) +{ + xmlAttrs["path"] = pos.file; + xmlAttrs["line"] = (format("%1%") % pos.line).str(); + xmlAttrs["column"] = (format("%1%") % pos.column).str(); +} + + +static void showAttrs(EvalState & state, bool strict, bool location, + Bindings & attrs, XMLWriter & doc, PathSet & context, PathSet & drvsSeen) +{ + StringSet names; + foreach (Bindings::iterator, i, attrs) + names.insert(i->first); + foreach (StringSet::iterator, i, names) { + Attr & a(attrs[state.symbols.create(*i)]); + + XMLAttrs xmlAttrs; + xmlAttrs["name"] = *i; + if (location && a.pos != &noPos) posToXML(xmlAttrs, *a.pos); + + XMLOpenElement _(doc, "attr", xmlAttrs); + printValueAsXML(state, strict, location, + a.value, doc, context, drvsSeen); + } +} + + +static void printValueAsXML(EvalState & state, bool strict, bool location, + Value & v, XMLWriter & doc, PathSet & context, PathSet & drvsSeen) +{ + checkInterrupt(); + + if (strict) state.forceValue(v); + + switch (v.type) { + + case tInt: + doc.writeEmptyElement("int", singletonAttrs("value", (format("%1%") % v.integer).str())); + break; + + case tBool: + doc.writeEmptyElement("bool", singletonAttrs("value", v.boolean ? "true" : "false")); + break; + + case tString: + /* !!! show the context? */ + doc.writeEmptyElement("string", singletonAttrs("value", v.string.s)); + break; + + case tPath: + doc.writeEmptyElement("path", singletonAttrs("value", v.path)); + break; + + case tNull: + doc.writeEmptyElement("null"); + break; + + case tAttrs: + if (state.isDerivation(v)) { + XMLAttrs xmlAttrs; + + Bindings::iterator a = v.attrs->find(state.symbols.create("derivation")); + + Path drvPath; + a = v.attrs->find(state.sDrvPath); + if (a != v.attrs->end()) { + if (strict) state.forceValue(a->second.value); + if (a->second.value.type == tString) + xmlAttrs["drvPath"] = drvPath = a->second.value.string.s; + } + + a = v.attrs->find(state.sOutPath); + if (a != v.attrs->end()) { + if (strict) state.forceValue(a->second.value); + if (a->second.value.type == tString) + xmlAttrs["outPath"] = a->second.value.string.s; + } + + XMLOpenElement _(doc, "derivation", xmlAttrs); + + if (drvPath != "" && drvsSeen.find(drvPath) == drvsSeen.end()) { + drvsSeen.insert(drvPath); + showAttrs(state, strict, location, *v.attrs, doc, context, drvsSeen); + } else + doc.writeEmptyElement("repeated"); + } + + else { + XMLOpenElement _(doc, "attrs"); + showAttrs(state, strict, location, *v.attrs, doc, context, drvsSeen); + } + + break; + + case tList: { + XMLOpenElement _(doc, "list"); + for (unsigned int n = 0; n < v.list.length; ++n) + printValueAsXML(state, strict, location, *v.list.elems[n], doc, context, drvsSeen); + break; + } + + case tLambda: { + XMLAttrs xmlAttrs; + if (location) posToXML(xmlAttrs, v.lambda.fun->pos); + XMLOpenElement _(doc, "function", xmlAttrs); + + if (v.lambda.fun->matchAttrs) { + XMLAttrs attrs; + if (!v.lambda.fun->arg.empty()) attrs["name"] = v.lambda.fun->arg; + if (v.lambda.fun->formals->ellipsis) attrs["ellipsis"] = "1"; + XMLOpenElement _(doc, "attrspat", attrs); + foreach (Formals::Formals_::iterator, i, v.lambda.fun->formals->formals) + doc.writeEmptyElement("attr", singletonAttrs("name", i->name)); + } else + doc.writeEmptyElement("varpat", singletonAttrs("name", v.lambda.fun->arg)); + + break; + } + + default: + doc.writeEmptyElement("unevaluated"); + } +} + + +void printValueAsXML(EvalState & state, bool strict, bool location, + Value & v, std::ostream & out, PathSet & context) +{ + XMLWriter doc(true, out); + XMLOpenElement root(doc, "expr"); + PathSet drvsSeen; + printValueAsXML(state, strict, location, v, doc, context, drvsSeen); +} + + +} diff --git a/src/libexpr/value-to-xml.hh b/src/libexpr/value-to-xml.hh new file mode 100644 index 0000000000..0c6de3a8b2 --- /dev/null +++ b/src/libexpr/value-to-xml.hh @@ -0,0 +1,17 @@ +#ifndef __VALUE_TO_XML_H +#define __VALUE_TO_XML_H + +#include <string> +#include <map> + +#include "nixexpr.hh" +#include "eval.hh" + +namespace nix { + +void printValueAsXML(EvalState & state, bool strict, bool location, + Value & v, std::ostream & out, PathSet & context); + +} + +#endif /* !__VALUE_TO_XML_H */ |