Four tips for learning regular expressions

Look-around in regular expressions matches a LOCATION, not a set of characters.

Zach Dell, son of billionaire Michael Dell, thinks he can solve America's energy crisis.

There's one regex implementation that is 100% compatible with Perl, and that's Perl.

A character class with a single character may be easier to read than an escaped special character, e.g. [.] vs \.

New post: Regular expressions that cross lines https://t.co/4rcA7L9bF5

You started selling on Amazon to make money... Not to fight with buggy shipment tools and janky spreadsheets. Boxem makes it faster than ever to get back to the things that matter Try it free today:

Emacs does not support Perl-style lookahead/lookbehind expressions.

Capitalize 'foo' or 'bar' using Perl: s/foo|bar/\u$&/

Using regular expressions in Python

(?i) changes case sensitivity by modifying the regex itself rather than using a processing option like //i in Perl.

Endless outreach. Endless tents. Endless chaos. This is not compassion. @FreeUpFdn is building a model that restores the lives of the homeless and public safety. Be part of the solution.

(?i) makes a regular expression case-insensitive. Example: (?i)abc is the same as [aA][bB][cC].

In CSS, ^= means begins with, *= means contains anywhere, and $= means ends with.

CSS has a crude form of regex, selection operators ^=, *=, and $= analogous to the use of ^, *, and $ in regex.

The acronym PCRE stands for 'Perl Compatible Regular Expressions'.

Today we're announcing a partnership with Cursor on Cursor Hooks. Hooks let you extend your agents with custom scripts. The Runlayer Hook gives you full visibility, control and security for every MCP call. Engineers just keep shipping.

*?, +?, and ?? are lazy quantifiers. The regexp engine will attempt to match as few tokens as possible.

In Perl, \A matches the beginning of a string and \z matches the end of a string. Removes ambiguity of lines vs strings.

Emacs regex escape |, (, and ). For example, (a|b) in Perl becomes \(a\|b\) in Emacs.

Flatten JSON files so they're easier to grep:

Graphemes

To group without capturing, use (?: ... ).

It's like Linktree, but it looks like a Framer or Webflow site. Claim your free domain before someone else takes it!

“Regular expressions aren’t random jumbles of punctuation—they’re carefully thought-out jumbles of punctuation!” -- The Perl Cookbook

\> represents an ending word boundary and match a position between two tokens. Some engines don't support this.