Catch a pointless self-assignment (like x = x;).
Groups & backrefs⚡⚡⚡⚡⚡
Groups & backrefs⚡⚡⚡⚡⚡
Catch · 0/5
· space→ tab- name·=·name;Target
- x·=·x;Target
- n·=·n;Target
- self·=·self;Target
- cache·=·cache;Target
Spare · 0 hit
- cache·=·cache[0];Innocent
- sum=sum;Innocent
- recache·=·cache;Innocent
- n·=·n·;Innocent
- self2·=·self;Innocent
Your pattern
Discussion
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A daily regex game
What is Regex Hunter?
Regex Hunter is a free daily regex puzzle, like Wordle for regular expressions: everyone gets the same hunt each day, and you write the shortest regex that catches every target word and spares the rest. It takes a few minutes, runs in your browser and needs no sign-up. When you want more, there are 20 practice packs, 9 Academy tracks and a regex cheat sheet.
How to play
Each hunt gives you two lists: targets your pattern must catch, and innocents it must spare. Type a regex, watch the words light up as they match, and refine it until every target is caught and every innocent is safe. Your score is the length of your pattern, so once it works, the real puzzle begins: trimming it down one character at a time.
A quick example
Catchcatcotcut
Sparecartcoatact
The pattern c.t catches all three targets and spares every innocent in just three characters. Real hunts get much harder, and you'll reach for character classes, anchors, alternation and lookarounds.
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