* Refactoring: move parseExprFromFile() and parseExprFromString() into

  the EvalState class.

10 files changed, 37 insertions, 52 deletions

diff --git a/src/libexpr/Makefile.am b/src/libexpr/Makefile.am
index f9da9ac01..c15975777 100644
--- a/src/libexpr/Makefile.am
+++ b/src/libexpr/Makefile.am
@@ -6,7 +6,7 @@ libexpr_la_SOURCES = \
  names.cc
 
 pkginclude_HEADERS = \
- nixexpr.hh eval.hh parser.hh lexer-tab.hh parser-tab.hh \
+ nixexpr.hh eval.hh lexer-tab.hh parser-tab.hh \
  get-drvs.hh attr-path.hh value-to-xml.hh common-opts.hh \
  names.hh symbol-table.hh
 
diff --git a/src/libexpr/common-opts.cc b/src/libexpr/common-opts.cc
index c364aa9cb..bab31f493 100644
--- a/src/libexpr/common-opts.cc
+++ b/src/libexpr/common-opts.cc
@@ -1,7 +1,6 @@
 #include "common-opts.hh"
 #include "../libmain/shared.hh"
 #include "util.hh"
-#include "parser.hh"
 
 
 namespace nix {
@@ -25,7 +24,7 @@ bool parseOptionArg(const string & arg, Strings::iterator & i,
     autoArgs.push_back(Attr(state.symbols.create(name), v));
 
     if (arg == "--arg")
-        state.mkThunk_(*v, parseExprFromString(state, value, absPath(".")));
+        state.mkThunk_(*v, state.parseExprFromString(value, absPath(".")));
     else
         mkString(*v, value);
 
diff --git a/src/libexpr/eval.cc b/src/libexpr/eval.cc
index acf5d7a8a..5701452f9 100644
--- a/src/libexpr/eval.cc
+++ b/src/libexpr/eval.cc
@@ -1,5 +1,4 @@
 #include "eval.hh"
-#include "parser.hh"
 #include "hash.hh"
 #include "util.hh"
 #include "store-api.hh"
@@ -427,14 +426,10 @@ void EvalState::evalFile(const Path & path, Value & v)
 {
     startNest(nest, lvlTalkative, format("evaluating file `%1%'") % path);
 
-    Expr * e = parseTrees[path];
-
-    if (!e) {
-        e = parseExprFromFile(*this, path);
-        parseTrees[path] = e;
-    }
+    Expr * e = parseExprFromFile(path);
     
     try {
+        /* !!! Maybe we should cache the evaluation result. */
         eval(e, v);
     } catch (Error & e) {
         addErrorPrefix(e, "while evaluating the file `%1%':\n", path);
diff --git a/src/libexpr/eval.hh b/src/libexpr/eval.hh
index 7b7fea934..e900217fa 100644
--- a/src/libexpr/eval.hh
+++ b/src/libexpr/eval.hh
@@ -218,6 +218,13 @@ public:
     EvalState();
     ~EvalState();
 
+    /* Parse a Nix expression from the specified file.  If `path'
+       refers to a directory, then "/default.nix" is appended. */
+    Expr * parseExprFromFile(Path path);
+
+    /* Parse a Nix expression from the specified string. */
+    Expr * parseExprFromString(const string & s, const Path & basePath);
+    
     /* Evaluate an expression read from the given file to normal
        form. */
     void evalFile(const Path & path, Value & v);
@@ -296,6 +303,9 @@ private:
     friend class ExprAttrs;
     friend class ExprLet;
 
+    Expr * parse(const char * text,
+        const Path & path, const Path & basePath);
+
 public:
     
     /* Do a deep equality test between two values.  That is, list
diff --git a/src/libexpr/parser.hh b/src/libexpr/parser.hh
deleted file mode 100644
index c8c8ad809..000000000
--- a/src/libexpr/parser.hh
+++ /dev/null
@@ -1,21 +0,0 @@
-#ifndef __PARSER_H
-#define __PARSER_H
-
-#include "eval.hh"
-
-
-namespace nix {
-
-
-/* Parse a Nix expression from the specified file.  If `path' refers
-   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);
-
-
-}
-
-
-#endif /* !__PARSER_H */
diff --git a/src/libexpr/parser.y b/src/libexpr/parser.y
index e5c586266..a64d327b4 100644
--- a/src/libexpr/parser.y
+++ b/src/libexpr/parser.y
@@ -450,11 +450,11 @@ formal
 namespace nix {
       
 
-static Expr * parse(EvalState & state, const char * text,
+Expr * EvalState::parse(const char * text,
     const Path & path, const Path & basePath)
 {
     yyscan_t scanner;
-    ParseData data(state.symbols);
+    ParseData data(symbols);
     data.basePath = basePath;
     data.path = path;
 
@@ -466,7 +466,7 @@ static Expr * parse(EvalState & state, const char * text,
     if (res) throw ParseError(data.error);
 
     try {
-        data.result->bindVars(state.staticBaseEnv);
+        data.result->bindVars(staticBaseEnv);
     } catch (Error & e) {
         throw ParseError(format("%1%, in `%2%'") % e.msg() % path);
     }
@@ -475,7 +475,7 @@ static Expr * parse(EvalState & state, const char * text,
 }
 
 
-Expr * parseExprFromFile(EvalState & state, Path path)
+Expr * EvalState::parseExprFromFile(Path path)
 {
     assert(path[0] == '/');
 
@@ -493,15 +493,21 @@ Expr * parseExprFromFile(EvalState & state, Path path)
     if (S_ISDIR(st.st_mode))
         path = canonPath(path + "/default.nix");
 
-    /* Read and parse the input file. */
-    return parse(state, readFile(path).c_str(), path, dirOf(path));
+    /* Read and parse the input file, unless it's already in the parse
+       tree cache. */
+    Expr * e = parseTrees[path];
+    if (!e) {
+        e = parse(readFile(path).c_str(), path, dirOf(path));
+        parseTrees[path] = e;
+    }
+
+    return e;
 }
 
 
-Expr * parseExprFromString(EvalState & state,
-    const string & s, const Path & basePath)
+Expr * EvalState::parseExprFromString(const string & s, const Path & basePath)
 {
-    return parse(state, s.c_str(), "(string)", basePath);
+    return parse(s.c_str(), "(string)", basePath);
 }
 
  
diff --git a/src/libexpr/primops.cc b/src/libexpr/primops.cc
index 11c67e138..9d226a327 100644
--- a/src/libexpr/primops.cc
+++ b/src/libexpr/primops.cc
@@ -5,7 +5,6 @@
 #include "util.hh"
 #include "archive.hh"
 #include "value-to-xml.hh"
-#include "parser.hh"
 #include "names.hh"
 
 #include <sys/types.h>
@@ -1059,7 +1058,7 @@ void EvalState::createBaseEnv()
     /* 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, parseExprFromString(*this, s, "/"));
+    mkThunk_(v, parseExprFromString(s, "/"));
     addConstant("derivation", v);
 
     // Paths
diff --git a/src/nix-env/nix-env.cc b/src/nix-env/nix-env.cc
index 9cfc69547..4ea301def 100644
--- a/src/nix-env/nix-env.cc
+++ b/src/nix-env/nix-env.cc
@@ -3,7 +3,6 @@
 #include "globals.hh"
 #include "misc.hh"
 #include "shared.hh"
-#include "parser.hh"
 #include "eval.hh"
 #include "help.txt.hh"
 #include "get-drvs.hh"
@@ -129,7 +128,7 @@ static void getAllExprs(EvalState & state,
             if (hasSuffix(attrName, ".nix"))
                 attrName = string(attrName, 0, attrName.size() - 4);
             attrs.attrs[state.symbols.create(attrName)] =
-                ExprAttrs::AttrDef(parseExprFromFile(state, absPath(path2)), noPos);
+                ExprAttrs::AttrDef(state.parseExprFromFile(absPath(path2)), noPos);
         }
         else
             /* `path2' is a directory (with no default.nix in it);
@@ -141,7 +140,7 @@ static void getAllExprs(EvalState & state,
 
 static Expr * loadSourceExpr(EvalState & state, const Path & path)
 {
-    if (isNixExpr(path)) return parseExprFromFile(state, absPath(path));
+    if (isNixExpr(path)) return state.parseExprFromFile(absPath(path));
 
     /* The path is a directory.  Put the Nix expressions in the
        directory in an attribute set, with the file name of each
@@ -354,7 +353,7 @@ static void queryInstSources(EvalState & state,
             Expr * e1 = loadSourceExpr(state, instSource.nixExprPath);
 
             foreach (Strings::const_iterator, i, args) {
-                Expr * e2 = parseExprFromString(state, *i, absPath("."));
+                Expr * e2 = state.parseExprFromString(*i, absPath("."));
                 Expr * call = new ExprApp(e2, e1);
                 Value v; state.eval(call, v);
                 getDerivations(state, v, "", instSource.autoArgs, elems);
diff --git a/src/nix-env/user-env.cc b/src/nix-env/user-env.cc
index 865d24e2f..670052bcb 100644
--- a/src/nix-env/user-env.cc
+++ b/src/nix-env/user-env.cc
@@ -5,7 +5,6 @@
 #include "globals.hh"
 #include "shared.hh"
 #include "eval.hh"
-#include "parser.hh"
 #include "profiles.hh"
 
 
@@ -24,7 +23,7 @@ DrvInfos queryInstalled(EvalState & state, const Path & userEnv)
 
     if (pathExists(manifestFile)) {
         Value v;
-        state.eval(parseExprFromFile(state, manifestFile), v);
+        state.evalFile(manifestFile, v);
         Bindings bindings;
         getDerivations(state, v, "", bindings, elems);
     } else if (pathExists(oldManifestFile))
@@ -113,7 +112,7 @@ bool createUserEnv(EvalState & state, DrvInfos & elems,
 
     /* Get the environment builder expression. */
     Value envBuilder;
-    state.eval(parseExprFromFile(state, nixDataDir + "/nix/corepkgs/buildenv"), envBuilder);
+    state.evalFile(nixDataDir + "/nix/corepkgs/buildenv", envBuilder);
 
     /* Construct a Nix expression that calls the user environment
        builder with the manifest as argument. */
diff --git a/src/nix-instantiate/nix-instantiate.cc b/src/nix-instantiate/nix-instantiate.cc
index 3d3b643cf..1f9059539 100644
--- a/src/nix-instantiate/nix-instantiate.cc
+++ b/src/nix-instantiate/nix-instantiate.cc
@@ -1,7 +1,6 @@
 #include "globals.hh"
 #include "shared.hh"
 #include "eval.hh"
-#include "parser.hh"
 #include "get-drvs.hh"
 #include "attr-path.hh"
 #include "value-to-xml.hh"
@@ -28,7 +27,7 @@ static Expr * parseStdin(EvalState & state)
     startNest(nest, lvlTalkative, format("parsing standard input"));
     string s, s2;
     while (getline(std::cin, s2)) s += s2 + "\n";
-    return parseExprFromString(state, s, absPath("."));
+    return state.parseExprFromString(s, absPath("."));
 }
 
 
@@ -139,7 +138,7 @@ void run(Strings args)
 
     foreach (Strings::iterator, i, files) {
         Path path = absPath(*i);
-        Expr * e = parseExprFromFile(state, path);
+        Expr * e = state.parseExprFromFile(path);
         processExpr(state, attrPaths, parseOnly, strict, autoArgs,
             evalOnly, xmlOutput, xmlOutputSourceLocation, e);
     }