nl_tokens: bidirectionally links two entries of the LRU linked list
pl_tokens: function <mask> ( nextEntry , prevEntry ) { if ( nextEntry !== prevEntry ) { if ( nextEntry ) nextEntry . p = prevEntry ; //p stands for previous, 'prev' didn't minify if ( prevEntry ) prevEntry . n = nextEntry ; //n stands for next, 'next' didn't minify } }