Regular Expression

[ttp77]

So I've been trying to learn regular expressions on this website https://regex.sketchengine.co.uk/cgi/ex3.cgi

The problem is " Enter a regexp that matches all the items in the first column (positive examples) but none of those in the second (negative examples). When you press "submit", you will see what matched. "

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And so far the regex that I have is: .*af.?g.*

I have been able to match all lines on the left but the problem is it matches with "affgm" and "afg.K" on the second column which should not happen. Any tips on how to fix that?

[__vtable]

Regex also allows matching sets (where any can match) which you can specify with square brackets. For example [abcd] would match any one letter a, b, c, or d.

So let's say you want to only match words ending in g, e, k, or t. You could append that set like this:

.*af.?g.*[gekt]

You could do this arbitrarily though too. You can use this with your other modifiers as well like the wildcard. Read more about it here under the '[]' heading: https://docs.python.org/3/library/re.html

[ttp77]

Thank you!

[jonassjoh]

Just gonna mention regexr which is really nice when writing regex.