I am importing javascript like below

var imported = document.createElement('script');
imported.src = 'script.js';
document.head.appendChild(imported);

In my script.js I have following code

Array.prototype.hasMin = function (attrib) {
  return (
    (this.length &&
      this.reduce(function (prev, curr) {
        return prev[attrib] < curr[attrib] ? prev : curr;
      })) ||
    null
  );
};

When i Just use the above code in script tag its working normally , but when i use it via appendchild method , I get following error

Uncaught Error: Syntax error, unrecognized expression: #function (attrib) {