#100DaysOfCode in Python Transcripts
Chapter: Days 28-30: Regular Expressions
Lecture: Second day: write your own regexes
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Welcome back to 100 days of Python. This is the second day of the 3 day regEx blog. And today I want to give you some pointers
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to get more familiar with regxxes and start to write your own. So we did an article, 10 Tips to Get More Out of Your RegExes.
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I recommend you read through it. One thing I didn't touch on is greediness, which is important and can prevent nasty bugs.
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And if you're still more a beginner in regex land, there's a nice talk at the end by Al Sweigart. Who by the way wrote an awesome Python beginner book,
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called How to Automate the Boring Stuff, and it's called Yes, It's Time to Learn Regular Expressions. And that gives you a very nice overview
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of regular expressions. Secondly, there's a nice how-to on the Python documentation page. Very refreshing how-to.
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I read this when I wrote the 10 Tips post, it's pretty dense, but it is a very good primer into regular expression,
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and what all the specific syntaxes mean, etc. If that's too much reading, which I can totally get, there's a nice online RegEx tester.
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And you just select Python, and you can write here your regular expression, and test it in real time.
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For example, I have some HTML with two paragraphs. And let's experiment a little bit with that greediness I mentioned. So let's match all of it.
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So that's greediness because it takes everything from the starting paragraph tag to the ending one. If I do a question mark, the match becomes shorter.
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It only takes the first paragraph. And you see all this nice feedback and explanations here. So that's a really great tool to experiment
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writing regular expressions in Python, because you get instant feedback. So that will be the third resource I have for you today.
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Just spend 20 or 30 minutes experimenting with regexes, and you'll see that they become a lot easier. Good luck.