As either example grows in complexity, they both wash down to a check and a call to another method to do the heavy lifting. In that case, the length of the methods will not grow apart from each other heavily.

And let me be clear. My gripe is only with the example. Not the idea. I happen to like pattern matching, but have never used it like those. Usually I use it to tease apart data by parts. (though, to be fair, I have found I use it less than I thought I did. Not sure why...)