nl_tokens: Creates a shallow copy of this collection
pl_tokens: function ( ) { var me = this , copy = new this . self ( ) , keys = me . keys , items = me . items , i = 0 , ln = items . length ; for ( ; i < ln ; i ++ ) { copy . add ( keys [ i ] , <mask> [ i ] ) ; } copy . getKey = me . getKey ; return copy ; }