var toInteger = require('../internals/to-integer'); var toString = require('../internals/to-string'); var requireObjectCoercible = require('../internals/require-object-coercible'); // `String.prototype.codePointAt` methods implementation var createMethod = function (CONVERT_TO_STRING) { return function ($this, pos) { var S = toString(requireObjectCoercible($this)); var position = toInteger(pos); var size = S.length; var first, second; if (position < 0 || position >= size) return CONVERT_TO_STRING ? '' : undefined; first = S.charCodeAt(position); return first < 0xD800 || first > 0xDBFF || position + 1 === size || (second = S.charCodeAt(position + 1)) < 0xDC00 || second > 0xDFFF ? CONVERT_TO_STRING ? S.charAt(position) : first : CONVERT_TO_STRING ? S.slice(position, position + 2) : (first - 0xD800 << 10) + (second - 0xDC00) + 0x10000; }; }; module.exports = { // `String.prototype.codePointAt` method // https://tc39.es/ecma262/#sec-string.prototype.codepointat codeAt: createMethod(false), // `String.prototype.at` method // https://github.com/mathiasbynens/String.prototype.at charAt: createMethod(true) };