nl_tokens: Reduce the items in an iterable down to a single instance of initial type returning the final result result of the reduction
pl_tokens: function reduce ( predicate , initial ) { return function ( iterable ) { let index = 0 ; let prevState = initial ; for ( const value of iterable ) { prevState = predicate ( prevState , value , index ) ; <mask> = index + 1 ; } return prevState ; } ; }