| 'use strict'; | 
|   | 
| var GetIntrinsic = require('get-intrinsic'); | 
|   | 
| var $TypeError = GetIntrinsic('%TypeError%'); | 
|   | 
| var callBound = require('call-bind/callBound'); | 
|   | 
| var $charCodeAt = callBound('String.prototype.charCodeAt'); | 
| var $numberToString = callBound('Number.prototype.toString'); | 
| var $toLowerCase = callBound('String.prototype.toLowerCase'); | 
| var $strSlice = callBound('String.prototype.slice'); | 
|   | 
| // https://262.ecma-international.org/9.0/#sec-unicodeescape | 
|   | 
| module.exports = function UnicodeEscape(C) { | 
|     if (typeof C !== 'string' || C.length !== 1) { | 
|         throw new $TypeError('Assertion failed: `C` must be a single code unit'); | 
|     } | 
|     var n = $charCodeAt(C, 0); | 
|     if (n > 0xFFFF) { | 
|         throw new $TypeError('`Assertion failed: numeric value of `C` must be <= 0xFFFF'); | 
|     } | 
|   | 
|     return '\\u' + $strSlice('0000' + $toLowerCase($numberToString(n, 16)), -4); | 
| }; |