* Don't create thunks for simple constants (integers, strings, paths)

  and allocate them only once.
* Move Value and related functions into value.hh.

1 files changed, 1 insertions, 111 deletions

diff --git a/src/libexpr/eval.hh b/src/libexpr/eval.hh
index 75438f5eba..91004fe4ca 100644
--- a/src/libexpr/eval.hh
+++ b/src/libexpr/eval.hh
@@ -1,6 +1,7 @@
 #ifndef __EVAL_H
 #define __EVAL_H
 
+#include "value.hh"
 #include "nixexpr.hh"
 #include "symbol-table.hh"
 #include "hash.hh"
@@ -16,8 +17,6 @@ namespace nix {
 
 
 class EvalState;
-struct Env;
-struct Value;
 struct Attr;
 
 
@@ -38,23 +37,6 @@ public:
 };
 
 
-typedef enum {
-    tInt = 1,
-    tBool,
-    tString,
-    tPath,
-    tNull,
-    tAttrs,
-    tList,
-    tThunk,
-    tApp,
-    tLambda,
-    tBlackhole,
-    tPrimOp,
-    tPrimOpApp,
-} ValueType;
-
-
 typedef void (* PrimOpFun) (EvalState & state, Value * * args, Value & v);
 
 
@@ -68,64 +50,6 @@ struct PrimOp
 };
 
 
-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;
-        PrimOp * primOp;
-        struct {
-            Value * left, * right;
-        } primOpApp;
-    };
-};
-
-
 struct Env
 {
     Env * up;
@@ -149,41 +73,7 @@ struct Attr
 };
 
 
-/* After overwriting an app node, be sure to clear pointers in the
-   Value to ensure that the target isn't kept alive unnecessarily. */
-static inline void clearValue(Value & v)
-{
-    v.app.right = 0;
-}
-
-
-static inline void mkInt(Value & v, int n)
-{
-    clearValue(v);
-    v.type = tInt;
-    v.integer = n;
-}
-
-
-static inline void mkBool(Value & v, bool b)
-{
-    clearValue(v);
-    v.type = tBool;
-    v.boolean = b;
-}
-
-
-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);
 
 void copyContext(const Value & v, PathSet & context);