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-rw-r--r--src/nix-instantiate/eval.cc265
1 files changed, 0 insertions, 265 deletions
diff --git a/src/nix-instantiate/eval.cc b/src/nix-instantiate/eval.cc
deleted file mode 100644
index b110c3a4a41c..000000000000
--- a/src/nix-instantiate/eval.cc
+++ /dev/null
@@ -1,265 +0,0 @@
-#include "eval.hh"
-#include "parser.hh"
-#include "primops.hh"
-
-
-EvalState::EvalState()
-    : normalForms(32768, 75)
-{
-    blackHole = ATmake("BlackHole()");
-    if (!blackHole) throw Error("cannot build black hole");
-    nrEvaluated = nrCached = 0;
-}
-
-
-/* Substitute an argument set into the body of a function. */
-static Expr substArgs(Expr body, ATermList formals, Expr arg)
-{
-    ATMatcher m;
-    ATermMap subs;
-    Expr undefined = ATmake("Undefined");
-
-    /* Get the formal arguments. */
-    for (ATermIterator i(formals); i; ++i) {
-        Expr name, def;
-        if (atMatch(m, *i) >> "NoDefFormal" >> name)
-            subs.set(name, undefined);
-        else if (atMatch(m, *i) >> "DefFormal" >> name >> def)
-            subs.set(name, def);
-        else abort(); /* can't happen */
-    }
-
-    /* Get the actual arguments, and check that they match with the
-       formals. */
-    ATermMap args;
-    queryAllAttrs(arg, args);
-    for (ATermIterator i(args.keys()); i; ++i) {
-        Expr key = *i;
-        Expr cur = subs.get(key);
-        if (!cur)
-            throw badTerm(format("function has no formal argument `%1%'")
-                % aterm2String(key), arg);
-        subs.set(key, args.get(key));
-    }
-
-    /* Check that all arguments are defined. */
-    for (ATermIterator i(subs.keys()); i; ++i)
-        if (subs.get(*i) == undefined)
-            throw badTerm(format("formal argument `%1%' missing")
-                % aterm2String(*i), arg);
-    
-    return substitute(subs, body);
-}
-
-
-/* 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}'. */
-ATerm expandRec(ATerm e, ATermList bnds)
-{
-    ATMatcher m;
-
-    /* Create the substitution list. */
-    ATermMap subs;
-    for (ATermIterator i(bnds); i; ++i) {
-        string s;
-        Expr e2;
-        if (!(atMatch(m, *i) >> "Bind" >> s >> e2))
-            abort(); /* can't happen */
-        subs.set(s, ATmake("Select(<term>, <str>)", e, s.c_str()));
-    }
-
-    /* Create the non-recursive set. */
-    ATermMap as;
-    for (ATermIterator i(bnds); i; ++i) {
-        string s;
-        Expr e2;
-        if (!(atMatch(m, *i) >> "Bind" >> s >> e2))
-            abort(); /* can't happen */
-        as.set(s, substitute(subs, e2));
-    }
-
-    return makeAttrs(as);
-}
-
-
-string evalString(EvalState & state, Expr e)
-{
-    e = evalExpr(state, e);
-    ATMatcher m;
-    string s;
-    if (!(atMatch(m, e) >> "Str" >> s))
-        throw badTerm("string expected", e);
-    return s;
-}
-
-
-Path evalPath(EvalState & state, Expr e)
-{
-    e = evalExpr(state, e);
-    ATMatcher m;
-    string s;
-    if (!(atMatch(m, e) >> "Path" >> s))
-        throw badTerm("path expected", e);
-    return s;
-}
-
-
-bool evalBool(EvalState & state, Expr e)
-{
-    e = evalExpr(state, e);
-    ATMatcher m;
-    if (atMatch(m, e) >> "Bool" >> "True") return true;
-    else if (atMatch(m, e) >> "Bool" >> "False") return false;
-    else throw badTerm("expecting a boolean", e);
-}
-
-
-Expr evalExpr2(EvalState & state, Expr e)
-{
-    ATMatcher m;
-    Expr e1, e2, e3, e4;
-    string s1;
-
-    /* Normal forms. */
-    if (atMatch(m, e) >> "Str" ||
-        atMatch(m, e) >> "Path" ||
-        atMatch(m, e) >> "Uri" ||
-        atMatch(m, e) >> "Bool" ||
-        atMatch(m, e) >> "Function" ||
-        atMatch(m, e) >> "Attrs" ||
-        atMatch(m, e) >> "List")
-        return e;
-
-    /* Any encountered variables must be undeclared or primops. */
-    if (atMatch(m, e) >> "Var" >> s1) {
-        if (s1 == "null") return primNull(state);
-        return e;
-    }
-
-    /* Function application. */
-    if (atMatch(m, e) >> "Call" >> e1 >> e2) {
-
-        ATermList formals;
-        
-        /* Evaluate the left-hand side. */
-        e1 = evalExpr(state, e1);
-
-        /* Is it a primop or a function? */
-        if (atMatch(m, e1) >> "Var" >> s1) {
-            if (s1 == "import") return primImport(state, e2);
-            if (s1 == "derivation") return primDerivation(state, e2);
-            if (s1 == "toString") return primToString(state, e2);
-            if (s1 == "baseNameOf") return primBaseNameOf(state, e2);
-            if (s1 == "isNull") return primIsNull(state, e2);
-            else throw badTerm("undefined variable/primop", e1);
-        }
-
-        else if (atMatch(m, e1) >> "Function" >> formals >> e4)
-            return evalExpr(state, 
-                substArgs(e4, formals, evalExpr(state, e2)));
-        
-        else throw badTerm("expecting a function or primop", e1);
-    }
-
-    /* Attribute selection. */
-    if (atMatch(m, e) >> "Select" >> e1 >> s1) {
-        Expr a = queryAttr(evalExpr(state, e1), s1);
-        if (!a) throw badTerm(format("missing attribute `%1%'") % s1, e);
-        return evalExpr(state, a);
-    }
-
-    /* Mutually recursive sets. */
-    ATermList bnds;
-    if (atMatch(m, e) >> "Rec" >> bnds)
-        return expandRec(e, bnds);
-
-    /* Let expressions `let {..., body = ...}' are just desugared
-       into `(rec {..., body = ...}).body'. */
-    if (atMatch(m, e) >> "LetRec" >> bnds)
-        return evalExpr(state, ATmake("Select(Rec(<term>), \"body\")", bnds));
-
-    /* Conditionals. */
-    if (atMatch(m, e) >> "If" >> e1 >> e2 >> e3) {
-        if (evalBool(state, e1))
-            return evalExpr(state, e2);
-        else
-            return evalExpr(state, e3);
-    }
-
-    /* Assertions. */
-    if (atMatch(m, e) >> "Assert" >> e1 >> e2) {
-        if (!evalBool(state, e1)) throw badTerm("guard failed", e);
-        return evalExpr(state, e2);
-    }
-
-    /* Generic equality. */
-    if (atMatch(m, e) >> "OpEq" >> e1 >> e2)
-        return makeBool(evalExpr(state, e1) == evalExpr(state, e2));
-
-    /* Generic inequality. */
-    if (atMatch(m, e) >> "OpNEq" >> e1 >> e2)
-        return makeBool(evalExpr(state, e1) != evalExpr(state, e2));
-
-    /* Negation. */
-    if (atMatch(m, e) >> "OpNot" >> e1)
-        return makeBool(!evalBool(state, e1));
-
-    /* Implication. */
-    if (atMatch(m, e) >> "OpImpl" >> e1 >> e2)
-        return makeBool(!evalBool(state, e1) || evalBool(state, e2));
-
-    /* Conjunction (logical AND). */
-    if (atMatch(m, e) >> "OpAnd" >> e1 >> e2)
-        return makeBool(evalBool(state, e1) && evalBool(state, e2));
-
-    /* Disjunction (logical OR). */
-    if (atMatch(m, e) >> "OpOr" >> e1 >> e2)
-        return makeBool(evalBool(state, e1) || evalBool(state, e2));
-
-    /* Barf. */
-    throw badTerm("invalid expression", e);
-}
-
-
-Expr evalExpr(EvalState & state, Expr e)
-{
-    startNest(nest, lvlVomit,
-        format("evaluating expression: %1%") % e);
-
-    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 == state.blackHole)
-            throw badTerm("infinite recursion", e);
-        state.nrCached++;
-        return nf;
-    }
-
-    /* Otherwise, evaluate and memoize. */
-    state.normalForms.set(e, state.blackHole);
-    nf = evalExpr2(state, e);
-    state.normalForms.set(e, nf);
-    return nf;
-}
-
-
-Expr evalFile(EvalState & state, const Path & path)
-{
-    startNest(nest, lvlTalkative, format("evaluating file `%1%'") % path);
-    Expr e = parseExprFromFile(path);
-    return evalExpr(state, e);
-}
-
-
-void printEvalStats(EvalState & state)
-{
-    debug(format("evaluated %1% expressions, %2% cache hits, %3%%% efficiency")
-        % state.nrEvaluated % state.nrCached
-        % ((float) state.nrCached / (float) state.nrEvaluated * 100));
-}