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POPython idiom to return first item or None
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copied!<p>I'm sure there's a simpler way of doing this that's just not occurring to me.</p> <p>I'm calling a bunch of methods that return a list. The list may be empty. If the list is non-empty, I want to return the first item; otherwise, I want to return None. This code works:</p> <pre><code>my_list = get_list() if len(my_list) > 0: return my_list[0] return None </code></pre> <p>It seems to me that there should be a simple one-line idiom for doing this, but for the life of me I can't think of it. Is there?</p> <p><strong>Edit:</strong></p> <p>The reason that I'm looking for a one-line expression here is not that I like incredibly terse code, but because I'm having to write a lot of code like this:</p> <pre><code>x = get_first_list() if x: # do something with x[0] # inevitably forget the [0] part, and have a bug to fix y = get_second_list() if y: # do something with y[0] # inevitably forget the [0] part AGAIN, and have another bug to fix </code></pre> <p>What I'd like to be doing can certainly be accomplished with a function (and probably will be):</p> <pre><code>def first_item(list_or_none): if list_or_none: return list_or_none[0] x = first_item(get_first_list()) if x: # do something with x y = first_item(get_second_list()) if y: # do something with y </code></pre> <p>I posted the question because I'm frequently surprised by what simple expressions in Python can do, and I thought that writing a function was a silly thing to do if there was a simple expression could do the trick. But seeing these answers, it seems like a function <em>is</em> the simple solution.</p>

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