mapbox/tilemill — pull request #983 by Vertice (2011-12-01 14:37:08+00:00)
Title: making use of caching of JSV schema instances. 

Rewrote the code for more clarity and added comments. The existing code depends on you to add a model.schema.id field as a caching key to avoid having to rebuild the schema every time validate is called.

the new code uses the this.constructor.title as the cache key if no model.schema.id is found.