frog: better errors/warnigns about type annotations in map literals.

frog/minfrog

 #!/usr/bin/env node
 //  ********** Library dart:core **************
 //  ********** Natives dart:core **************
 /**
  * Generates a dynamic call stub for a function.
  * Our goal is to create a stub method like this on-the-fly:
  *   function($0, $1, capture) { return this($0, $1, true, capture); }
  *
  * This stub then replaces the dynamic one on Function, with one that is
  * specialized for that particular function, taking into account its default
@@ skipping 9365 matching lines @@
 Parser.prototype.finishTypedLiteral = function(start, isConst) {
   var span = this._makeSpan(start);
   var typeToBeNamedLater = new NameTypeReference(false, null, null, span);
   var genericType = this.addTypeArguments(typeToBeNamedLater, 0);
   if (this._peekKind(4/*TokenKind.LBRACK*/) || this._peekKind(56/*TokenKind.INDEX*/)) {
     genericType.set$baseType(new TypeReference(span, $globals.world.listType));
     return this.finishListLiteral(start, isConst, genericType);
   }
   else if (this._peekKind(6/*TokenKind.LBRACE*/)) {
     genericType.set$baseType(new TypeReference(span, $globals.world.mapType));
-    if ($ne(genericType.get$typeArguments().length, 1)) {
-      this._error('a map literal takes one type argument specfying the value type', $eq(genericType.get$typeArguments().length, 0) ? genericType.get$typeArguments().get$span() : genericType.get$typeArguments().$index(1).get$span());
+    if ($eq(genericType.get$typeArguments().length, 1)) {
+      genericType.set$typeArguments([new TypeReference(span, $globals.world.stringType), genericType.get$typeArguments().$index(0)]);
     }
-    genericType.set$typeArguments([new TypeReference(span, $globals.world.stringType), genericType.get$typeArguments().$index(0)]);
+    else if ($eq(genericType.get$typeArguments().length, 2)) {
+      var keyType = genericType.get$typeArguments().$index(0);
+      if (!(keyType instanceof NameTypeReference) || keyType.get$name().get$name() !== "String") {
+        $globals.world.error('the key type of a map literal is implicitly "String"', keyType.get$span());
+      }
+      else {
+        $globals.world.warning('a map literal takes one type argument specifying the value type', keyType.get$span());
+      }
+    }
     return this.finishMapLiteral(start, isConst, genericType);
   }
   else {
     this._errorExpected('array or map literal');
   }
 }
 Parser.prototype._readModifiers = function() {
   var modifiers = null;
   while (true) {
     switch (this._peek()) {
@@ skipping 3735 matching lines @@
   $globals._MAGENTA_COLOR = '\u001b[35m';
   $globals._NO_COLOR = '\u001b[0m';
   $globals._RED_COLOR = '\u001b[31m';
 }
 var const$0 = new NoMoreElementsException()/*const NoMoreElementsException()*/;
 var const$2 = new EmptyQueueException()/*const EmptyQueueException()*/;
 var const$3 = new _DeletedKeySentinel()/*const _DeletedKeySentinel()*/;
 var $globals = {};
 $static_init();
 main();