nl_tokens: Get a buffer with the length encoding .
pl_tokens: function getLengthEncoding ( n , special ) { if ( n < 0 ) throw new Error ( 'Cannot write negative length encoding: ' + n ) ; if ( ! special ) { if ( n <= 0x3F ) { return new Buffer ( [ n ] ) ; } else if ( n <= 0x3FFF ) { return new Buffer ( [ 0x40 | ( n >> 8 ) , n & 0xFF ] ) ; } else if ( n <= 0xFFFFFFFF ) { var buffer = new Buffer ( 5 ) ; buffer . writeUInt8 ( 0x80 , 0 ) ; <mask> . writeUInt32BE ( n , 1 ) ; return buffer ; } throw new Error ( 'Failed to write length encoding: ' + n ) ; } else { if ( n > 0x3F ) { throw new Error ( 'Cannot encode ' + n + ' using special length encoding' ) ; } return new Buffer ( [ 0xC0 | n ] ) ; } }