Early draft of strict mode

src/scopes.cc

Index: src/scopes.cc
diff --git a/src/scopes.cc b/src/scopes.cc
index 3565e11b58f710e280f1080c0fb479e5e01376f9..d359ccd27cbdc055d329e622e5fa8c865c61e4a5 100644
--- a/src/scopes.cc
+++ b/src/scopes.cc
@@ -412,6 +412,31 @@ int Scope::ContextChainLength(Scope* scope) {
   return n;
 }
 
+bool Scope::HasDuplicateParameterName() {
+  int length = params_.length();
+  HashMap map(Match, &HashMap::DefaultAllocator, length * 2);

[Lasse Reichstein, 2011/01/13 07:18:40]

If the length is short (e.g., five or less), just do the quadratic comparison.
We are comparing symbols, so it's pretty quick, and I'm guessing that the
average number of arguments to a function is around two (could be a fun thing to
check :).

[Martin Maly, 2011/01/14 00:06:28]

Done.

[Lasse Reichstein, 2011/01/14 11:42:05]

And thinking more about it, just do the simple thing in all cases.

[Martin Maly, 2011/01/14 16:30:43]

Done.

+  for (int i = 0; i < length; i ++) {
+    Handle<String> name = params_[i]->name();
+    HashMap::Entry* p = map.Lookup(name.location(), name->Hash(), true);
+    if (p->value == NULL) {
+      p->value = name.location();
+    } else {
+      // Duplicate found!
+      return true;
+    }
+  }
+  return false;
+}
+
+bool Scope::HasEvalOrArgumentsParameter() {
+  for (int i = 0, length = params_.length(); i < length; i++) {
+    Handle<String> name = params_[i]->name();
+    if (name.is_identical_to(Factory::arguments_symbol()) ||
+        name.is_identical_to(Factory::eval_symbol()))
+      return true;
+  }
+  return false;
+}
 
 #ifdef DEBUG
 static const char* Header(Scope::Type type) {