nl_tokens: Apply all operations reducing them to retain : n for n the number of items in the array .
pl_tokens: function ( callback ) { var items = [ ] , offset = 0 ; forEach ( this . _operations , function ( arrayOperation ) { callback ( arrayOperation . items , offset , arrayOperation . type ) ; if ( arrayOperation . type !== DELETE ) { offset += arrayOperation . count ; items = <mask> . concat ( arrayOperation . items ) ; } } ) ; this . _operations = [ new ArrayOperation ( RETAIN , items . length , items ) ] ; }