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-rw-r--r--src/libexpr/eval.cc42
-rw-r--r--src/libexpr/eval.hh2
-rw-r--r--src/libexpr/nixexpr.cc9
-rw-r--r--src/libexpr/nixexpr.hh13
4 files changed, 31 insertions, 35 deletions
diff --git a/src/libexpr/eval.cc b/src/libexpr/eval.cc
index d93447010..ccd359ba7 100644
--- a/src/libexpr/eval.cc
+++ b/src/libexpr/eval.cc
@@ -236,24 +236,17 @@ void mkPath(Value & v, const char * s)
}
-Value * EvalState::lookupVar(Env * env, const Symbol & name)
+Value * EvalState::lookupVar(Env * env, const VarRef & var)
{
-#if 0
- /* First look for a regular variable binding for `name'. */
- Bindings::iterator i = env2->bindings.find(name);
- if (i != env2->bindings.end()) return &i->second;
- }
-
- /* Otherwise, look for a `with' attribute set containing `name'.
- Inner `withs' take precedence (i.e. `with {x=1;}; with {x=2;};
- x' evaluates to 2). */
- for (Env * env2 = env; env2; env2 = env2->up) {
- Bindings::iterator i = env2->bindings.find(sWith);
- if (i == env2->bindings.end()) continue;
- Bindings::iterator j = i->second.attrs->find(name);
- if (j != i->second.attrs->end()) return &j->second;
- }
-#endif
+ for (unsigned int l = var.level; l; --l, env = env->up) ;
+
+ if (var.fromWith) {
+ Bindings::iterator j = env->values[0].attrs->find(var.name);
+ if (j == env->values[0].attrs->end())
+ throwEvalError("undefined variable `%1%'", var.name);
+ return &j->second;
+ } else
+ return &env->values[var.displ];
}
@@ -481,18 +474,9 @@ void ExprList::eval(EvalState & state, Env & env, Value & v)
void ExprVar::eval(EvalState & state, Env & env, Value & v)
{
- Env * env2 = &env;
- for (unsigned int l = level; l; --l, env2 = env2->up) ;
-
- if (fromWith) {
- Bindings::iterator j = env2->values[0].attrs->find(name);
- if (j == env2->values[0].attrs->end())
- throwEvalError("undefined variable `%1%'", name);
- v = j->second;
- } else {
- state.forceValue(env2->values[displ]);
- v = env2->values[displ];
- }
+ Value * v2 = state.lookupVar(&env, info);
+ state.forceValue(*v2);
+ v = *v2;
}
diff --git a/src/libexpr/eval.hh b/src/libexpr/eval.hh
index a24b7345e..bc61c84ea 100644
--- a/src/libexpr/eval.hh
+++ b/src/libexpr/eval.hh
@@ -238,7 +238,7 @@ private:
void addPrimOp(const string & name,
unsigned int arity, PrimOp primOp);
- Value * lookupVar(Env * env, const Symbol & name);
+ Value * lookupVar(Env * env, const VarRef & var);
friend class ExprVar;
friend class ExprAttrs;
diff --git a/src/libexpr/nixexpr.cc b/src/libexpr/nixexpr.cc
index ab4fa6cba..03b849a38 100644
--- a/src/libexpr/nixexpr.cc
+++ b/src/libexpr/nixexpr.cc
@@ -38,7 +38,7 @@ void ExprPath::show(std::ostream & str)
void ExprVar::show(std::ostream & str)
{
- str << name;
+ str << info.name;
}
void ExprSelect::show(std::ostream & str)
@@ -157,7 +157,7 @@ void ExprPath::bindVars(const StaticEnv & env)
{
}
-void ExprVar::bindVars(const StaticEnv & env)
+void VarRef::bind(const StaticEnv & env)
{
/* Check whether the variable appears in the environment. If so,
set its level and displacement. */
@@ -187,6 +187,11 @@ void ExprVar::bindVars(const StaticEnv & env)
this->level = withLevel;
}
+void ExprVar::bindVars(const StaticEnv & env)
+{
+ info.bind(env);
+}
+
void ExprSelect::bindVars(const StaticEnv & env)
{
e->bindVars(env);
diff --git a/src/libexpr/nixexpr.hh b/src/libexpr/nixexpr.hh
index f9ed34f58..ffea7049f 100644
--- a/src/libexpr/nixexpr.hh
+++ b/src/libexpr/nixexpr.hh
@@ -78,7 +78,7 @@ struct ExprPath : Expr
COMMON_METHODS
};
-struct ExprVar : Expr
+struct VarRef
{
Symbol name;
@@ -94,8 +94,15 @@ struct ExprVar : Expr
levels up from the current one.*/
unsigned int level;
unsigned int displ;
-
- ExprVar(const Symbol & name) : name(name) { };
+
+ VarRef(const Symbol & name) : name(name) { };
+ void bind(const StaticEnv & env);
+};
+
+struct ExprVar : Expr
+{
+ VarRef info;
+ ExprVar(const Symbol & name) : info(name) { };
COMMON_METHODS
};