IsStringPrefix.js
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'use strict';
var GetIntrinsic = require('../GetIntrinsic');
var $TypeError = GetIntrinsic('%TypeError%');
var isPrefixOf = require('../helpers/isPrefixOf');
// var callBound = require('../helpers/callBound');
// var $charAt = callBound('String.prototype.charAt');
var Type = require('./Type');
// https://www.ecma-international.org/ecma-262/9.0/#sec-isstringprefix
module.exports = function IsStringPrefix(p, q) {
if (Type(p) !== 'String') {
throw new $TypeError('Assertion failed: "p" must be a String');
}
if (Type(q) !== 'String') {
throw new $TypeError('Assertion failed: "q" must be a String');
}
return isPrefixOf(p, q);
/*
if (p === q || p === '') {
return true;
}
var pLength = p.length;
var qLength = q.length;
if (pLength >= qLength) {
return false;
}
// assert: pLength < qLength
for (var i = 0; i < pLength; i += 1) {
if ($charAt(p, i) !== $charAt(q, i)) {
return false;
}
}
return true;
*/
};