nl_tokens: makes the entry the freshEnd of the LRU linked list
pl_tokens: function refresh ( <mask> ) { if ( entry !== freshEnd ) { if ( ! staleEnd ) { staleEnd = entry ; } else if ( staleEnd === entry ) { staleEnd = entry . n ; } link ( entry . n , entry . p ) ; link ( entry , freshEnd ) ; freshEnd = entry ; freshEnd . n = null ; } }