title: Uncaught TypeError: $ is not a function in core-js
body: <p>I'm trying to install the <a href="https://medium.com/bigcommerce-developer-blog/bigcommerce-checkout-is-now-open-source-39e823bc5b3b" rel="nofollow noreferrer">BigCommerce Open Checkout</a> script, and I'm currently getting this error when I try to run the basic installation locally:</p>
  <pre><code>Uncaught TypeError: $ is not a function
  at eval (es.array.index-of.js?c975:15)
  at Object../node_modules/core-js/modules/es.array.index-of.js
  </code></pre>
  <p>That file is:</p>
  <pre><code>'use strict';
  var $ = require('../internals/export');
  var $indexOf = require('../internals/array-includes').indexOf;
  var arrayMethodIsStrict = require('../internals/array-method-is-strict');
  var arrayMethodUsesToLength = require('../internals/array-method-uses-to-length');
  
  var nativeIndexOf = [].indexOf;
  
  var NEGATIVE_ZERO = !!nativeIndexOf &amp;&amp; 1 / [1].indexOf(1, -0) &lt; 0;
  var STRICT_METHOD = arrayMethodIsStrict('indexOf');
  var USES_TO_LENGTH = arrayMethodUsesToLength('indexOf', { ACCESSORS: true, 1: 0 });
  
  // `Array.prototype.indexOf` method
  // https://tc39.github.io/ecma262/#sec-array.prototype.indexof
  $({ target: 'Array', proto: true, forced: NEGATIVE_ZERO || !STRICT_METHOD || !USES_TO_LENGTH }, {
    indexOf: function indexOf(searchElement /* , fromIndex = 0 */) {
      return NEGATIVE_ZERO
        // convert -0 to +0
        ? nativeIndexOf.apply(this, arguments) || 0
        : $indexOf(this, searchElement, arguments.length &gt; 1 ? arguments[1] : undefined);
    }
  });
  </code></pre>
  <p>So far, I've tried updating core-js and NPM repeatedly with no luck.</p>