* Working evaluator.

* Mutually recursive attribute sets.
* Print evaluator efficiency statistics.

1 files changed, 19 insertions, 300 deletions

diff --git a/src/fix-ng/fix.cc b/src/fix-ng/fix.cc
index fb98dc6978..d791461bd5 100644
--- a/src/fix-ng/fix.cc
+++ b/src/fix-ng/fix.cc
@@ -9,7 +9,6 @@
 
 
 #if 0
-#if 0
 static Path searchPath(const Paths & searchDirs, const Path & relPath)
 {
     if (string(relPath, 0, 1) == "/") return relPath;
@@ -28,178 +27,9 @@ static Path searchPath(const Paths & searchDirs, const Path & relPath)
 #endif
 
 
-static Expr substExpr(string x, Expr rep, Expr e)
-{
-    char * s;
-    Expr e2;
-
-    if (ATmatch(e, "Var(<str>)", &s))
-        if (x == s)
-            return rep;
-        else
-            return e;
-
-    ATermList formals;
-    if (ATmatch(e, "Function([<list>], <term>)", &formals, &e2)) {
-        while (!ATisEmpty(formals)) {
-            if (!ATmatch(ATgetFirst(formals), "<str>", &s))
-                throw badTerm("not a list of formals", (ATerm) formals);
-            if (x == (string) s)
-                return e;
-            formals = ATgetNext(formals);
-        }
-    }
-
-    /* Generically substitute in subterms. */
-
-    if (ATgetType(e) == AT_APPL) {
-        AFun fun = ATgetAFun(e);
-        int arity = ATgetArity(fun);
-        ATermList args = ATempty;
-
-        for (int i = arity - 1; i >= 0; i--)
-            args = ATinsert(args, substExpr(x, rep, ATgetArgument(e, i)));
-        
-        return (ATerm) ATmakeApplList(fun, args);
-    }
-
-    if (ATgetType(e) == AT_LIST) {
-        ATermList in = (ATermList) e;
-        ATermList out = ATempty;
-
-        while (!ATisEmpty(in)) {
-            out = ATinsert(out, substExpr(x, rep, ATgetFirst(in)));
-            in = ATgetNext(in);
-        }
-
-        return (ATerm) ATreverse(out);
-    }
-
-    throw badTerm("do not know how to substitute", e);
-}
-
-
-static Expr substExprMany(ATermList formals, ATermList args, Expr body)
-{
-    char * s;
-    Expr e;
-
-    /* !!! check args against formals */
-
-    while (!ATisEmpty(args)) {
-        ATerm tup = ATgetFirst(args);
-        if (!ATmatch(tup, "(<str>, <term>)", &s, &e))
-            throw badTerm("expected an argument tuple", tup);
-
-        body = substExpr(s, e, body);
-
-        args = ATgetNext(args);
-    }
-    
-    return body;
-}
-
-
-static PathSet nixExprRootsCached(EvalState & state, const Path & nePath)
-{
-    PkgPaths::iterator i = state.pkgPaths.find(nePath);
-    if (i != state.pkgPaths.end())
-        return i->second;
-    else {
-        PathSet paths = nixExprRoots(nePath);
-        state.pkgPaths[nePath] = paths;
-        return paths;
-    }
-}
-
-
-static Hash hashPackage(EvalState & state, NixExpr ne)
-{
-    if (ne.type == NixExpr::neDerivation) {
-	PathSet inputs2;
-        for (PathSet::iterator i = ne.derivation.inputs.begin();
-             i != ne.derivation.inputs.end(); i++)
-        {
-            PkgHashes::iterator j = state.pkgHashes.find(*i);
-            if (j == state.pkgHashes.end())
-                throw Error(format("don't know expression `%1%'") % (string) *i);
-            inputs2.insert(j->second);
-        }
-	ne.derivation.inputs = inputs2;
-    }
-    return hashTerm(unparseNixExpr(ne));
-}
-
-
-static string processBinding(EvalState & state, Expr e, NixExpr & ne)
-{
-    char * s1;
-
-    if (ATmatch(e, "NixExpr(<str>)", &s1)) {
-        Path nePath(s1);
-        PathSet paths = nixExprRootsCached(state, nePath);
-        if (paths.size() != 1) abort();
-        Path path = *(paths.begin());
-        ne.derivation.inputs.insert(nePath);
-        return path;
-    }
-    
-    if (ATmatch(e, "<str>", &s1))
-        return s1;
-
-    if (ATmatch(e, "True")) return "1";
-    
-    if (ATmatch(e, "False")) return "";
-
-    ATermList l;
-    if (ATmatch(e, "[<list>]", &l)) {
-	string s;
-	bool first = true;
-        while (!ATisEmpty(l)) {
-	    if (!first) s = s + " "; else first = false;
-	    s += processBinding(state, evalExpr(state, ATgetFirst(l)), ne);
-            l = ATgetNext(l);
-        }
-	return s;
-    }
-    
-    throw badTerm("invalid package binding", e);
-}
-
-
+#if 0
 static Expr evalExpr2(EvalState & state, Expr e)
 {
-    char * s1;
-    Expr e1, e2, e3, e4;
-    ATermList bnds;
-
-    /* Normal forms. */
-    if (ATmatch(e, "<str>", &s1) ||
-        ATmatch(e, "[<list>]", &e1) ||
-        ATmatch(e, "True") ||
-        ATmatch(e, "False") ||
-        ATmatch(e, "Function([<list>], <term>)", &e1, &e2) ||
-        ATmatch(e, "NixExpr(<str>)", &s1))
-        return e;
-
-    try {
-        Hash pkgHash = hashPackage(state, parseNixExpr(e));
-        Path pkgPath = writeTerm(e, "");
-        state.pkgHashes[pkgPath] = pkgHash;
-        return ATmake("NixExpr(<str>)", pkgPath.c_str());
-    } catch (...) { /* !!! catch parse errors only */
-    }
-
-    /* Application. */
-    if (ATmatch(e, "Call(<term>, [<list>])", &e1, &e2) ||
-        ATmatch(e, "App(<term>, [<list>])", &e1, &e2)) {
-        e1 = evalExpr(state, e1);
-        if (!ATmatch(e1, "Function([<list>], <term>)", &e3, &e4))
-            throw badTerm("expecting a function", e1);
-        return evalExpr(state,
-            substExprMany((ATermList) e3, (ATermList) e2, e4));
-    }
-
     /* Conditional. */
     if (ATmatch(e, "If(<term>, <term>, <term>)", &e1, &e2, &e3)) {
         e1 = evalExpr(state, e1);
@@ -226,127 +56,6 @@ static Expr evalExpr2(EvalState & state, Expr e)
             ATmake("True") : ATmake("False");
     }
 
-    /* Platform constant. */
-    if (ATmatch(e, "Platform")) {
-        return ATmake("<str>", thisSystem.c_str());
-    }
-
-    /* Fix inclusion. */
-    if (ATmatch(e, "IncludeFix(<str>)", &s1)) {
-        Path fileName(s1);
-        return evalFile(state, s1);
-    }
-
-    /* Relative files. */
-    if (ATmatch(e, "Relative(<str>)", &s1)) {
-        Path srcPath = s1;
-        Path dstPath = addToStore(srcPath);
-
-        ClosureElem elem;
-        NixExpr ne;
-        ne.type = NixExpr::neClosure;
-        ne.closure.roots.insert(dstPath);
-        ne.closure.elems[dstPath] = elem;
-
-        Hash pkgHash = hashPackage(state, ne);
-        Path pkgPath = writeTerm(unparseNixExpr(ne), "");
-        state.pkgHashes[pkgPath] = pkgHash;
-
-        msg(lvlChatty, format("copied `%1%' -> closure `%2%'")
-            % srcPath % pkgPath);
-
-        return ATmake("NixExpr(<str>)", pkgPath.c_str());
-    }
-
-    /* Packages are transformed into Nix derivation expressions. */
-    if (ATmatch(e, "Package([<list>])", &bnds)) {
-
-        /* Evaluate the bindings and put them in a map. */
-        map<string, ATerm> bndMap;
-        bndMap["platform"] = ATmake("<str>", thisSystem.c_str());
-        while (!ATisEmpty(bnds)) {
-            ATerm bnd = ATgetFirst(bnds);
-            if (!ATmatch(bnd, "(<str>, <term>)", &s1, &e1))
-                throw badTerm("binding expected", bnd);
-            bndMap[s1] = evalExpr(state, e1);
-            bnds = ATgetNext(bnds);
-        }
-
-        /* Gather information for building the derivation
-           expression. */
-        NixExpr ne;
-        ne.type = NixExpr::neDerivation;
-        ne.derivation.platform = thisSystem;
-        string name;
-        Path outPath;
-        Hash outHash;
-        bool outHashGiven = false;
-        bnds = ATempty;
-
-        for (map<string, ATerm>::iterator it = bndMap.begin();
-             it != bndMap.end(); it++)
-        {
-            string key = it->first;
-            ATerm value = it->second;
-
-            if (key == "args") {
-                ATermList args;
-                if (!ATmatch(value, "[<list>]", &args))
-                    throw badTerm("list expected", value);
-                
-                while (!ATisEmpty(args)) {
-                    Expr arg = evalExpr(state, ATgetFirst(args));
-                    ne.derivation.args.push_back(processBinding(state, arg, ne));
-                    args = ATgetNext(args);
-                }
-            }
-
-            else {
-                string s = processBinding(state, value, ne);
-                ne.derivation.env[key] = s;
-
-                if (key == "build") ne.derivation.builder = s;
-                if (key == "name") name = s;
-                if (key == "outPath") outPath = s;
-                if (key == "id") { 
-                    outHash = parseHash(s);
-                    outHashGiven = true;
-                }
-            }
-
-            bnds = ATinsert(bnds, 
-                ATmake("(<str>, <term>)", key.c_str(), value));
-        }
-
-        if (ne.derivation.builder == "")
-            throw badTerm("no builder specified", e);
-        
-        if (name == "")
-            throw badTerm("no package name specified", e);
-        
-        /* Determine the output path. */
-        if (!outHashGiven) outHash = hashPackage(state, ne);
-        if (outPath == "")
-            /* Hash the Nix expression with no outputs to produce a
-               unique but deterministic path name for this package. */
-            outPath = 
-                canonPath(nixStore + "/" + ((string) outHash).c_str() + "-" + name);
-        ne.derivation.env["out"] = outPath;
-        ne.derivation.outputs.insert(outPath);
-
-        /* Write the resulting term into the Nix store directory. */
-        Hash pkgHash = outHashGiven
-            ? hashString((string) outHash + outPath)
-            : hashPackage(state, ne);
-        Path pkgPath = writeTerm(unparseNixExpr(ne), "-d-" + name);
-        state.pkgHashes[pkgPath] = pkgHash;
-
-        msg(lvlChatty, format("instantiated `%1%' -> `%2%'")
-            % name % pkgPath);
-
-        return ATmake("NixExpr(<str>)", pkgPath.c_str());
-    }
-
     /* BaseName primitive function. */
     if (ATmatch(e, "BaseName(<term>)", &e1)) {
         e1 = evalExpr(state, e1);
@@ -355,8 +64,6 @@ static Expr evalExpr2(EvalState & state, Expr e)
         return ATmake("<str>", baseNameOf(s1).c_str());
     }
 
-    /* Barf. */
-    throw badTerm("invalid expression", e);
 }
 #endif
 
@@ -374,17 +81,27 @@ static Expr evalStdin(EvalState & state)
 static void printNixExpr(EvalState & state, Expr e)
 {
     ATermList es;
-    char * s;
-    if (ATmatch(e, "NixExpr(<str>)", &s)) {
-        cout << format("%1%\n") % s;
-    } 
-    else if (ATmatch(e, "[<list>]", &es)) {
+
+    if (ATmatch(e, "Attrs([<list>])", &es)) {
+        Expr a = queryAttr(e, "type");
+        if (a && evalString(state, a) == "derivation") {
+            a = queryAttr(e, "drvPath");
+            if (a) {
+                cout << format("%1%\n") % evalPath(state, a);
+                return;
+            }
+        }
+    }
+
+    if (ATmatch(e, "[<list>]", &es)) {
         while (!ATisEmpty(es)) {
             printNixExpr(state, evalExpr(state, ATgetFirst(es)));
             es = ATgetNext(es);
         }
+        return;
     }
-    else throw badTerm("top level does not evaluate to a (list of) Nix expression(s)", e);
+
+    throw badTerm("top level does not evaluate to one or more Nix expressions", e);
 }
 
 
@@ -435,6 +152,8 @@ void run(Strings args)
         Expr e = evalFile(state, absPath(*it));
         printNixExpr(state, e);
     }
+
+    printEvalStats(state);
 }