jquery: validate if element is empty before applying effect... is it necessary?
<p>in jQuery, is it necessary to check if the variable contains something or jQuery does it by itself... let me explain with an example:</p>

<pre><code>var image = $(placeholder).children('img');


// if placeholder contains image, hide it!
if (image.length) {
   alert('found one, hide it!');
   $(image).fadeOut(400);
}

... more code here...
</code></pre>

<p>i've realize that just writing the following works the same...</p>

<pre><code>var image = $(placeholder).children('img');
$(image).fadeOut(400);
</code></pre>

<p>i mean, is it good practice to do a check first or let jquery handle it?</p>
