Download - The Bastards Book of Regular Expressions

A better Find-and-Replace 22Using Rubular.com to find just the standalone ‘cat‘In the scenario of the mixed-up dates, the pattern we want to match is: The number “2012”, if it ispreceded by a “1/”, one-or-two other numbers, and another “/”Without regexes, you have to fix these problems by hand. This might not be a problem if it’s just acouple of words. Even manually performing a dozen Find-and-Replaces to fix every variation of aword is tedious, at worst.But if you have a hundreds or thousands of fixes? Then tedious becomes painful or even impossible.There’s more than find-and-replaceBig deal, right? Being able to find-and-replace better is hardly something worth reading a wholebook for. And if all I had to show you was text-replacement tricks, I’d agree.But if you’re a real data-gatherer or information-seeker, the real power of regular expressions is tofind if and where patterns exist at all. Maybe you have a list of a million invoices that can’t be putin Excel and you need to quickly filter for the six-figure amounts. Or you have a 500-page PDF andyou need a fast hack to highlight proper nouns, such as names of people and places.In these cases, you don’t know precisely what you’re looking for until you find it. But you do knowthe patterns. With regular expressions, you’ll have a way to describe and actually use those patterns.