Hello. I hope a topic is self describing. I'm new on your site, it helped me much times but this time i was surprised not to find an answer on internet. The question is quite simple. Say, i have an element created in code:

    var elem = docuemnt.createElement('div');
    ...

I wish sometime to check have i placed it into the DOM before or it is still virtual.

    // check if elem is placed in the DOM (it's not)

    document.getElementByTagName('body')[0].appendChild(elem);
    // check - and it's finally in the document

When use jquery i can write '$(elem).filter(':visible') or even $(elem).visible() if i remember correctly. But if it's based on the same javascript, then... All i want is to check does the element exist only virtually or it can be found in a document (and still may be not visible).