[strong] Deprecate for-in

src/parser.cc

Index: src/parser.cc
diff --git a/src/parser.cc b/src/parser.cc
index bb8cb52b75068f0aee6941880fd7d1ecfe58bd29..fdfa87a0e06f3202a0eeb0050ec435e3b75a3a54 100644
--- a/src/parser.cc
+++ b/src/parser.cc
@@ -2882,9 +2882,14 @@ WhileStatement* Parser::ParseWhileStatement(
 
 
 bool Parser::CheckInOrOf(bool accept_OF,

[marja, 2015/02/19 12:34:22]

... could you move CheckInOrOf to ParserBase, seems pretty unnecessary to have
it twice.

[rossberg, 2015/02/19 13:23:05]

Done.

-                         ForEachStatement::VisitMode* visit_mode) {
+                         ForEachStatement::VisitMode* visit_mode, bool* ok) {
   if (Check(Token::IN)) {
-    *visit_mode = ForEachStatement::ENUMERATE;
+    if (is_strong(language_mode())) {
+      ReportMessageAt(scanner()->location(), "strong_for_in");
+      *ok = false;
+    } else {
+      *visit_mode = ForEachStatement::ENUMERATE;
+    }
     return true;
   } else if (accept_OF && CheckContextualKeyword(CStrVector("of"))) {
     *visit_mode = ForEachStatement::ITERATE;
@@ -3222,7 +3227,8 @@ Statement* Parser::ParseForStatement(ZoneList<const AstRawString*>* labels,
       ForEachStatement::VisitMode mode;
       int each_pos = position();
 
-      if (name != NULL && CheckInOrOf(accept_OF, &mode)) {
+      if (name != NULL && CheckInOrOf(accept_OF, &mode, ok)) {
+        if (!*ok) return nullptr;
         ForEachStatement* loop =
             factory()->NewForEachStatement(mode, labels, stmt_pos);
         Target target(&this->target_stack_, loop);
@@ -3259,7 +3265,9 @@ Statement* Parser::ParseForStatement(ZoneList<const AstRawString*>* labels,
       ForEachStatement::VisitMode mode;
       int each_pos = position();
 
-      if (accept_IN && CheckInOrOf(accept_OF, &mode)) {
+      if (accept_IN && CheckInOrOf(accept_OF, &mode, ok)) {
+        if (!*ok) return nullptr;
+
         // Rewrite a for-in statement of the form
         //
         //   for (let/const x in e) b
@@ -3321,7 +3329,8 @@ Statement* Parser::ParseForStatement(ZoneList<const AstRawString*>* labels,
         expression->AsVariableProxy()->raw_name() ==
             ast_value_factory()->let_string();
 
-      if (CheckInOrOf(accept_OF, &mode)) {
+      if (CheckInOrOf(accept_OF, &mode, ok)) {
+        if (!*ok) return nullptr;
         expression = this->CheckAndRewriteReferenceExpression(
             expression, lhs_location, "invalid_lhs_in_for", CHECK_OK);