| 'use strict'; |
| |
| var GetIntrinsic = require('get-intrinsic'); |
| |
| var $TypeError = GetIntrinsic('%TypeError%'); |
| |
| var IsIntegralNumber = require('./IsIntegralNumber'); |
| var Type = require('./Type'); |
| |
| var callBound = require('call-bind/callBound'); |
| |
| var $slice = callBound('String.prototype.slice'); |
| |
| // https://262.ecma-international.org/12.0/#substring |
| module.exports = function substring(S, inclusiveStart, exclusiveEnd) { |
| if (Type(S) !== 'String' || !IsIntegralNumber(inclusiveStart) || (arguments.length > 2 && !IsIntegralNumber(exclusiveEnd))) { |
| throw new $TypeError('`S` must be a String, and `inclusiveStart` and `exclusiveEnd` must be integers'); |
| } |
| return $slice(S, inclusiveStart, arguments.length > 2 ? exclusiveEnd : S.length); |
| }; |