gistfile1.js

function gbDocument(docname) {

/* ..... */
    this.destroy = function() {
        // We've been destroyed! Best clean up our actions.
        pagehandler.removeDoc(this.name, $(".tablist"));

        console.log("I'm being deleted!");
        console.log(this);
        return undefined
    }
}

/* To be used like: */
session.documents['document name here'] = new gbDocument('document name here');

/* Then I'd use that document, when it's not needed: */
session.documents['document name here'] = session.documents['document name here'].destroy();
// Doesn't delete this, just sets it to undefined