nl_tokens: Derived from the 10 . 1 . 1 UTF16Encoding of the ES6 Spec .
pl_tokens: function utf16EncodeAsString ( codePoint ) { ts . Debug . assert ( 0x0 <= codePoint && codePoint <= 0x10FFFF ) ; if ( codePoint <= 65535 ) { return <mask> . fromCharCode ( codePoint ) ; } var codeUnit1 = Math . floor ( ( codePoint - 65536 ) / 1024 ) + 0xD800 ; var codeUnit2 = ( ( codePoint - 65536 ) % 1024 ) + 0xDC00 ; return String . fromCharCode ( codeUnit1 , codeUnit2 ) ; }