I assume you mean to compare it to:

    el.email = (function(){
        var input = document.createElement('input');
        input.type = "email";
        return input;
    })();

...or something similar. Your could also use createContextualFragement or a little function that uses innerHTML, both of which parse a string into HTML (which is problematic). Or you could use a templating library, of which there are many and this is one.