Regex to find A and not B on a line

python regex textmate
Zach picture Zach · Apr 9, 2010 · Viewed 7.8k times · Source

I'm looking for a regex to search my python program to find all lines where foo, but not bar, is passed into a method as a keyword argument. I'm playing around with lookahead and lookbehind assertions, but not having much luck.

Any help?

Thanks

Answer

Mark Byers picture Mark Byers · Apr 9, 2010

If you have a string foo that you want to find and another string bar that must not be present, you can use this:

^(?!.*bar).*foo

Creating a regular expression that exactly meets all your requirements is very difficult as Python code is not a regular language, but hopefully you should be able to use this as a starting point to get something good enough for your needs.

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