nl_tokens: Future class .
pl_tokens: function Future ( f , args ) { var self = this ; function run ( ) { args [ args . length ] = function cb ( ) { switch ( arguments . length ) { case 0 : self . result = null ; break ; case 1 : if ( arguments [ 0 ] instanceof Error ) { self . err = arguments [ 0 ] ; } else { self . result = arguments [ 0 ] ; } break ; default : self . err = arguments [ 0 ] ; if ( arguments . length === 2 ) { self . result = arguments [ 1 ] ; } else { self . result = Array . prototype . slice . call ( arguments , 1 ) ; } break ; } if ( self . flow_ ) self . flow_ . futureFinished ( ) ; var caller = self . caller ; if ( caller ) caller . run ( ) ; } ; args . length ++ ; f . apply ( undefined , args ) ; } this . run = run ; var flow = Fiber . current . flow ; if ( flow ) { Object . defineProperty ( this , "flow_" , { enumerable : false , writable : true , value : flow } ) ; flow . registerFuture ( this ) ; } else { <mask> ( ) ; } }