frog bug 642: type variables can't be used in allocations.

frog/gen.dart

 // Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 /**
  * Top level generator object for writing code and keeping track of
  * dependencies.
  *
  * Should have two compilation models, but only one implemented so far.
  *
@@ skipping 2091 matching lines @@
       typeRef = new NameTypeReference(
           typeRef.isFinal, typeRef.name, names, typeRef.span);
     }
 
     var type = method.resolveType(typeRef, true);
     if (type.isTop) {
       type = type.library.findTypeByName(constructorName);
       constructorName = '';
     }
 
+    if (method.isStatic
+        && ((method.typeParameters === null && type.hasTypeParams)

[Jennifer Messerly, 2011/12/06 22:14:55]

I don't understand the (method.typeParameters === null && type.hasTypeParams)
part

Also, could this just be one warning:

if (type is ParameterType) {
  world.error('cannot instantiate a type parameter', node.span);
   return _makeMissingValue(constructorName);
}

IMHO, there's not a lot of value in checking 2 things here.

However, we probably still need the other error, but it needs to happen
somewhere else (like resolveType?) because you can refer to a type in other ways
besides a "new", for example:

class SomeType<T> {
  static foo() {
    T t = bar(); // or "bar is T"
    return t; 
  }
}

The boolean parameter to resolveType is called "isRequired" but it really
*means* something along the lines of "isStaticContext"

+          || type is ParameterType)) {
+      world.error('using type parameter in static context', node.span);
+      return _makeMissingValue(constructorName);
+    } else if (type is ParameterType) {
+      world.error('cannot instantiate a type parameter', node.span);
+      return _makeMissingValue(constructorName);
+    }
+
     var m = type.getConstructor(constructorName);
     if (m == null) {
       var name = type.jsname;
       if (type.isVar) {
         name = typeRef.name.name;
       }
       world.error('no matching constructor for $name', node.span);
       return _makeMissingValue(name);
     }
 
@@ skipping 341 matching lines @@
       result.add(new Value(world.varType, '\$$i', null, /*needsTemp:*/false));
     }
     for (int i = bareCount; i < length; i++) {
       var name = getName(i);
       if (name == null) name = '\$$i';
       result.add(new Value(world.varType, name, null, /*needsTemp:*/false));
     }
     return new Arguments(nodes, result);
   }
 }