Create IterableMixinWorkaround and move most of the Collections methods there.

sdk/lib/collection/collections.dart

Index: sdk/lib/collection/collections.dart
diff --git a/sdk/lib/collection/collections.dart b/sdk/lib/collection/collections.dart
index 4bd1fadb513ce5e84a36fbb51ae347e2db93af69..146385b4ce9b757762511d69c7350e6209beb274 100644
--- a/sdk/lib/collection/collections.dart
+++ b/sdk/lib/collection/collections.dart
@@ -4,12 +4,7 @@
 
 part of dart.collection;
 

[Lasse Reichstein Nielsen, 2013/01/16 15:34:31]

Add comment describing purpose of class.

[floitsch, 2013/01/16 16:11:35]

Done.

-/**
- * The [Collections] class implements static methods useful when
- * writing a class that implements [Collection] and the [iterator]
- * method.
- */
-class Collections {
+class IterableMixinWorkaround {
   static bool contains(Iterable iterable, var element) {
     for (final e in iterable) {
       if (element == e) return true;
@@ -204,6 +199,41 @@ class Collections {
     return buffer.toString();
   }
 
+  static Iterable where(Iterable<Object> iterable, bool f(var element)) {
+    return new WhereIterable(iterable, f);

[Lasse Reichstein Nielsen, 2013/01/16 15:34:31]

Just make the first argument be type "Iterable" with no <Object>. It's being
used as dynamic when passed to 'f' anyway.

[floitsch, 2013/01/16 16:11:35]

Done.

+  }
+
+  static List mappedByList(List<Object> list, f(var element)) {
+    return new MappedList(list, f);
+  }
+
+  static List takeList(List<Object> list, int n) {
+    // TODO(floitsch): missing generic type.

[Lasse Reichstein Nielsen, 2013/01/16 15:34:31]

It's a workaround, it'll be fixed when we have mixins with type parameters.

[floitsch, 2013/01/16 16:11:35]

Replaced with normal comment.

+    return new ListView(list, 0, n);
+  }
+
+  static Iterable takeWhile(Iterable iterable, bool test(var value)) {
+    // TODO(floitsch): missing generic type.
+    return new TakeWhileIterable(iterable, test);
+  }
+
+  static List skipList(List<Object> list, int n) {
+    // TODO(floitsch): missing generic type.
+    return new ListView(list, n, null);
+  }
+
+  static Iterable skipWhile(Iterable iterable, bool test(var value)) {
+    // TODO(floitsch): missing generic type.
+    return new SkipWhileIterable(iterable, test);
+  }
+}
+
+/**
+ * The [Collections] class implements static methods useful when
+ * writing a class that implements [Collection] and the [iterator]
+ * method.
+ */
+class Collections {
   // TODO(jjb): visiting list should be an identityHashSet when it exists
 
   /**