Non-retaining Cocoa containers from Three20.

NonRetainingContainers.m

static const void *TTRetainNoOp(CFAllocatorRef allocator,
                                   const void *value) {return value;}


static void TTReleaseNoOp(CFAllocatorRef allocator,
                             const void *value) {}


NSMutableArray *TTCreateNonRetainingArray()
{
  CFArrayCallBacks callbacks = kCFTypeArrayCallBacks;
  callbacks.retain  =  TTRetainNoOp;
  callbacks.release = TTReleaseNoOp;
  return (NSMutableArray *)CFArrayCreateMutable(nil, 0, &callbacks);
}



NSMutableDictionary *TTCreateNonRetainingDictionary()
{
  CFDictionaryKeyCallBacks keyCallbacks =   kCFTypeDictionaryKeyCallBacks;
  CFDictionaryValueCallBacks  callbacks = kCFTypeDictionaryValueCallBacks;
  callbacks.retain  =  TTRetainNoOp;
  callbacks.release = TTReleaseNoOp;


  return (NSMutableDictionary *)CFDictionaryCreateMutable(nil, 0,
      &keyCallbacks, &callbacks);
}