Regex 101

Today I received an email from the store I used to work at asking me to make a printer friendly version of an online table of information.

As I learned more about regular expressions from the “INF3331” course I took this fall, solving this problem proved to be way easier than any previous attempts at the likes of it.

At times I’ve thought that regexes are harder to read and debug than ordinary programming languages, but with a good editor like Atom or the regex101 page, it all became a lot less stressful.

As far as editors go, I have to admit that I still use emacs when I’m not using an IDE or GUI-editor.

Note to self about regular expressions.

(.*?) to capture zero or more characters in a non-greedy manner

(?:.*?) for the same grouping without backreferences.

$1 or $[group-number] for backreferences in JavaScript and Atom

\1 or \[group-number] for backreferences in Python, PHP.

Perl and PHP also uses \g1 or \g[group-number] for backreferences.

The following characters need to be escaped in regex:


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