Add type information.

dart/site/try/poi/poi.dart

 // Copyright (c) 2014, 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.
 
 library trydart.poi;
 
 import 'dart:async' show
     Completer,
     Future,
     Stream;
@@ skipping 26 matching lines @@
     QueueFilter,
     WorkItem;
 
 import 'package:compiler/implementation/elements/visitor.dart' show
     ElementVisitor;
 
 import 'package:compiler/implementation/elements/elements.dart' show
     ClassElement,
     CompilationUnitElement,
     Element,
+    ElementCategory,
     LibraryElement,
     ScopeContainerElement;
 
+import 'package:compiler/implementation/dart_types.dart' show
+    DartType;
+
 import 'package:compiler/implementation/scanner/scannerlib.dart' show
     EOF_TOKEN,
     IDENTIFIER_TOKEN,
     KEYWORD_TOKEN,
     PartialClassElement,
     PartialElement,
     Token;
 
 /// Controls if this program should be querying Dart Mind. Used by tests.
 bool enableDartMind = true;
@@ skipping 300 matching lines @@
 
   void visitCompilationUnitElement(CompilationUnitElement e) {
     e.enclosingElement.accept(this);
   }
 
   void serialize(
       Element element,
       {bool omitEnclosing: true,
        void serializeMembers(),
        String name}) {
+    DartType type;
+    int category = element.kind.category;
+    if (category == ElementCategory.FUNCTION ||
+        category == ElementCategory.VARIABLE ||
+        element.isConstructor) {
+      type = element.computeType(cachedCompiler);
+    }
     if (name == null) {
       name = element.name;
     }
     buffer.write('{\n');
     indentationLevel++;
     indented
         ..write('"name": "')
         ..write(name)
         ..write('",\n');
     indented
         ..write('"kind": "')
         ..write(element.kind)
         ..write('"');
-    // TODO(ahe): Add a type/signature field.
+    if (type != null) {
+      buffer.write(',\n');
+      indented
+          ..write('"type": "')
+          ..write(type)
+          ..write('"');
+    }
     if (serializeMembers != null) {
       buffer.write(',\n');
       indented.write('"members": [');
       indentationLevel++;
       serializeMembers();
       indentationLevel--;
       buffer.write('\n');
       indented.write(']');
     }
     if (!omitEnclosing) {
       buffer.write(',\n');
       indented.write('"enclosing": ');
       element.enclosingElement.accept(this);
     }
     indentationLevel--;
     buffer.write('\n');
     indented.write('}');
   }
 }