nl_tokens: Fast array filter
pl_tokens: function filter ( arr , cb ) { if ( arr == null ) return [ ] ; if ( typeof cb !== 'function' ) { throw new TypeError ( 'braces: filter expects a callback function.' ) ; } var len = arr . length ; var res = arr . slice ( ) ; var i = 0 ; while ( len -- ) { if ( ! cb ( arr [ len ] , i ++ ) ) { <mask> . splice ( len , 1 ) ; } } return res ; }