Use UnmodifiableMapView in compiler

pkg/docgen/lib/src/models/class.dart

Index: pkg/docgen/lib/src/models/class.dart
diff --git a/pkg/docgen/lib/src/models/class.dart b/pkg/docgen/lib/src/models/class.dart
index 555b1ddb9cd6f22284e6edd4712ded743dbb72fe..4bcbb65433c9a0f7a1881a2d0e99ad055e93024b 100644
--- a/pkg/docgen/lib/src/models/class.dart
+++ b/pkg/docgen/lib/src/models/class.dart
@@ -4,6 +4,8 @@
 
 library docgen.models.clazz;
 
+import 'dart:collection';
+
 import '../exports/dart2js_mirrors.dart' as dart2js_mirrors;
 import '../exports/mirrors_util.dart' as dart2js_util;
 import '../exports/source_mirrors.dart';
@@ -86,8 +88,8 @@ class Class extends OwnedIndexable<dart2js_mirrors.Dart2JsInterfaceTypeMirror>
     interfaces = superinterfaces.toList();
     variables = createVariables(
         dart2js_util.variablesOf(classMirror.declarations), this);
-    methods = createMethods(classMirror.declarations.values.where(
-        (mirror) => mirror is MethodMirror), this);
+    methods = createMethods(new TypeOfIterable<MethodMirror>(

[herhut, 2014/04/28 08:24:41]

Maybe rather expose [anyMethodOf] and use that. Would remove the code
duplication from below and hide more of the inner workings in the mirror code
base.

[kevmoo, 2014/04/28 09:23:01]

Done.

+        classMirror.declarations.values), this);
 
     // Tell superclass that you are a subclass, unless you are not
     // visible or an intermediary mixin class.
@@ -243,3 +245,29 @@ class Class extends OwnedIndexable<dart2js_mirrors.Dart2JsInterfaceTypeMirror>
 
   bool isValidMirror(DeclarationMirror mirror) => mirror is ClassMirror;
 }
+
+class TypeOfIterable<TTarget> extends IterableBase<TTarget> {

[herhut, 2014/04/28 08:24:41]

Nit: I prefer using just T for the type variable because it reads easier.

+  final Iterable _source;
+
+  TypeOfIterable(this._source);
+
+  Iterator<TTarget> get iterator =>
+      new _TypeOfIterator<TTarget>(_source.iterator);
+}
+
+class _TypeOfIterator<TTarget> implements Iterator<TTarget> {
+  final Iterator _source;
+
+  TTarget get current => _source.current as TTarget;

[herhut, 2014/04/28 08:24:41]

Do you really need the runtime check via as here? By construction this should be
safe and in checked mode the return type will be checked.

+
+  _TypeOfIterator(this._source);
+
+  bool moveNext() {
+    while(_source.moveNext()) {
+      if (_source.current is TTarget) {
+        return true;
+      }
+    }
+    return false;
+  }
+}