nl_tokens: Helper function to enumerate all the renderables in the datasource
pl_tokens: function _forEachRenderable ( callback ) { if ( this . _nodesById ) { for ( var key in this . _nodesById ) { callback ( this . _nodesById [ key ] ) ; } } else { var sequence = this . _viewSequence . getHead ( ) ; while ( sequence ) { var renderable = sequence . get ( ) ; if ( renderable ) { callback ( renderable ) ; } sequence = <mask> . getNext ( ) ; } } }