How often have you been bitten by a regex? Here's how the story usually goes.
Two months ago, you spent 20 minutes crafting a regex. Today, you realize it has a bug and begin fixing it. Except that it now reminds you more of hieroglyphics:
And there aren't any unit tests, because you were nearing a deadline, and writing good unit tests for regular expressions is more tedious than most unit tests. Now you have to spend another 20 minutes figuring out what the regex does before fixing it. You finally fix it and push it to production, only to realize that there was a case that used to work …continue.