Function isFunction

src/modules/jquery.js:72–85

(obj)

  var support = {};

  var isFunction = function isFunction(obj) {
    // Support: Chrome <=57, Firefox <=52
    // In some browsers, typeof returns "function" for HTML <object> elements
    // (i.e., `typeof document.createElement( "object" ) === "function"`).
    // We don't want to classify *any* DOM node as a function.
    // Support: QtWeb <=3.8.5, WebKit <=534.34, wkhtmltopdf tool <=0.12.5
    // Plus for old WebKit, typeof returns "function" for HTML collections
    // (e.g., `typeof document.getElementsByTagName("div") === "function"`). (gh-4756)
    return (
      typeof obj === 'function' &&
      typeof obj.nodeType !== 'number' &&
      typeof obj.item !== 'function'
    );
  };

  var isWindow = function isWindow(obj) {
    return obj != null && obj === obj.window;