#100DaysOfCode in Python Transcripts
Chapter: Days 28-30: Regular Expressions
Lecture: Concepts: what did we learn
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So, let's do a quick wrap of what we've learned so far. When to not use regexes. Well if simple string operations do, use those.
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Re.search versus re.match, re.match matches the whole string, re.search matches part of the string. Those are probably the main methods
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you will be using on the re module. Capturing parentheses, to access part of the match use parentheses and you can use groups on the matching object
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to get to the string. Your new best friend findall, one of my favorites. To get all the occurrences of a pattern in a string,
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you can us findall and I showed you two examples. One is to get all the days or numbers out of the string
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and it returns a list, and findall combined with counter one line of code a lot of stuff gets done. Compile for regexes, so you can use re.compile
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to compile a regex to use over and over again. And you can add a verbose switch to make regular expressions
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none space sensitive so you can line 'em out over multiple lines, making 'em more readable. String replacements, resub.
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Again if you can use string replace do that but sometimes the pattern you want to match is more sophisticated and you need a regular expression.
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The way to use read outsub methods is to define your pattern. Again I prefer you using a raw string to not to escape the back slashes.
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And the second argument is to put in your replacement. And here's a little bit more advanced example. Where you use capturing parentheses to
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port part of the matching string to the replacement arguments. And now it's your turn.