From 403cb9327f5c298cb6a85a87241962df4a90857b Mon Sep 17 00:00:00 2001
From: Eelco Dolstra <e.dolstra@tudelft.nl>
Date: Thu, 30 Oct 2003 16:48:26 +0000
Subject: [PATCH] * Factor out evaluation into a separate file.

---
 src/fix-ng/Makefile.am |  2 +-
 src/fix-ng/eval.cc     | 45 +++++++++++++++++++++++++++++
 src/fix-ng/eval.hh     | 31 ++++++++++++++++++++
 src/fix-ng/fix.cc      | 65 +++++++-----------------------------------
 4 files changed, 87 insertions(+), 56 deletions(-)
 create mode 100644 src/fix-ng/eval.cc
 create mode 100644 src/fix-ng/eval.hh

diff --git a/src/fix-ng/Makefile.am b/src/fix-ng/Makefile.am
index 88f1f4fe9..b0e90450e 100644
--- a/src/fix-ng/Makefile.am
+++ b/src/fix-ng/Makefile.am
@@ -1,6 +1,6 @@
 bin_PROGRAMS = fix-ng
 
-fix_ng_SOURCES = fix-expr.cc parser.cc fix.cc
+fix_ng_SOURCES = fix-expr.cc parser.cc eval.cc fix.cc
 fix_ng_LDADD = ../libmain/libmain.a ../libnix/libnix.a ../boost/format/libformat.a \
  -L../../externals/inst/lib -ldb_cxx -lsglr -lATB -lconversion -lasfix2 -lmept -lATerm
 
diff --git a/src/fix-ng/eval.cc b/src/fix-ng/eval.cc
new file mode 100644
index 000000000..c0f4680a4
--- /dev/null
+++ b/src/fix-ng/eval.cc
@@ -0,0 +1,45 @@
+#include "eval.hh"
+#include "expr.hh"
+#include "parser.hh"
+
+
+EvalState::EvalState()
+{
+    blackHole = ATmake("BlackHole()");
+    if (!blackHole) throw Error("cannot build black hole");
+}
+
+
+Expr evalExpr2(EvalState & state, Expr e)
+{
+    return e;
+}
+
+
+Expr evalExpr(EvalState & state, Expr e)
+{
+    Nest nest(lvlVomit, format("evaluating expression: %1%") % printTerm(e));
+
+    /* Consult the memo table to quickly get the normal form of
+       previously evaluated expressions. */
+    NormalForms::iterator i = state.normalForms.find(e);
+    if (i != state.normalForms.end()) {
+        if (i->second == state.blackHole)
+            throw badTerm("infinite recursion", e);
+        return i->second;
+    }
+
+    /* Otherwise, evaluate and memoize. */
+    state.normalForms[e] = state.blackHole;
+    Expr nf = evalExpr2(state, e);
+    state.normalForms[e] = nf;
+    return nf;
+}
+
+
+Expr evalFile(EvalState & state, const Path & path)
+{
+    Nest nest(lvlTalkative, format("evaluating file `%1%'") % path);
+    Expr e = parseExprFromFile(path);
+    return evalExpr(state, e);
+}
diff --git a/src/fix-ng/eval.hh b/src/fix-ng/eval.hh
new file mode 100644
index 000000000..5fcb648a7
--- /dev/null
+++ b/src/fix-ng/eval.hh
@@ -0,0 +1,31 @@
+#ifndef __EVAL_H
+#define __EVAL_H
+
+#include <map>
+
+#include "fix-expr.hh"
+
+
+typedef map<Expr, Expr> NormalForms;
+//typedef map<Path, PathSet> PkgPaths;
+//typedef map<Path, Hash> PkgHashes;
+
+struct EvalState 
+{
+    NormalForms normalForms;
+    //    PkgPaths pkgPaths;
+    //    PkgHashes pkgHashes; /* normalised package hashes */
+    Expr blackHole;
+
+    EvalState();
+};
+
+
+/* Evaluate an expression to normal form. */
+Expr evalExpr(EvalState & state, Expr e);
+
+/* Evaluate an expression read from the given file to normal form. */
+Expr evalFile(EvalState & state, const Path & path);
+
+
+#endif /* !__EVAL_H */
diff --git a/src/fix-ng/fix.cc b/src/fix-ng/fix.cc
index 05e27c506..fb98dc697 100644
--- a/src/fix-ng/fix.cc
+++ b/src/fix-ng/fix.cc
@@ -1,36 +1,14 @@
 #include <map>
 #include <iostream>
 
-#include "parser.hh"
 #include "globals.hh"
 #include "normalise.hh"
 #include "shared.hh"
+#include "expr.hh"
+#include "eval.hh"
 
 
-typedef map<ATerm, ATerm> NormalForms;
-typedef map<Path, PathSet> PkgPaths;
-typedef map<Path, Hash> PkgHashes;
-
-struct EvalState 
-{
-    Paths searchDirs;
-    NormalForms normalForms;
-    PkgPaths pkgPaths;
-    PkgHashes pkgHashes; /* normalised package hashes */
-    Expr blackHole;
-
-    EvalState()
-    {
-        blackHole = ATmake("BlackHole()");
-        if (!blackHole) throw Error("cannot build black hole");
-    }
-};
-
-
-static Expr evalFile(EvalState & state, const Path & path);
-static Expr evalExpr(EvalState & state, Expr e);
-
-
+#if 0
 #if 0
 static Path searchPath(const Paths & searchDirs, const Path & relPath)
 {
@@ -380,35 +358,7 @@ static Expr evalExpr2(EvalState & state, Expr e)
     /* Barf. */
     throw badTerm("invalid expression", e);
 }
-
-
-static Expr evalExpr(EvalState & state, Expr e)
-{
-    Nest nest(lvlVomit, format("evaluating expression: %1%") % printTerm(e));
-
-    /* Consult the memo table to quickly get the normal form of
-       previously evaluated expressions. */
-    NormalForms::iterator i = state.normalForms.find(e);
-    if (i != state.normalForms.end()) {
-        if (i->second == state.blackHole)
-            throw badTerm("infinite recursion", e);
-        return i->second;
-    }
-
-    /* Otherwise, evaluate and memoize. */
-    state.normalForms[e] = state.blackHole;
-    Expr nf = evalExpr2(state, e);
-    state.normalForms[e] = nf;
-    return nf;
-}
-
-
-static Expr evalFile(EvalState & state, const Path & path)
-{
-    Nest nest(lvlTalkative, format("evaluating file `%1%'") % path);
-    Expr e = parseExprFromFile(path);
-    return evalExpr(state, e);
-}
+#endif
 
 
 static Expr evalStdin(EvalState & state)
@@ -444,20 +394,25 @@ void run(Strings args)
     Strings files;
     bool readStdin = false;
 
+#if 0
     state.searchDirs.push_back(".");
     state.searchDirs.push_back(nixDataDir + "/fix");
+#endif
     
     for (Strings::iterator it = args.begin();
          it != args.end(); )
     {
         string arg = *it++;
 
+#if 0
         if (arg == "--includedir" || arg == "-I") {
             if (it == args.end())
                 throw UsageError(format("argument required in `%1%'") % arg);
             state.searchDirs.push_back(*it++);
         }
-        else if (arg == "--verbose" || arg == "-v")
+        else
+#endif
+        if (arg == "--verbose" || arg == "-v")
             verbosity = (Verbosity) ((int) verbosity + 1);
         else if (arg == "-")
             readStdin = true;