Lane runner · real Python 3 in your browser
Match the pattern.
Pick the lane.
Every gate is a regular expression. Three lanes, three strings, and only one matches the whole pattern. Switch Rex into it before the gate reaches you. Each check runs re.fullmatch in real Python 3, and the console shows you exactly what Python said.
Score
0
Level
1 literals
Lives
Streak · best
0 · —
Regex Runner
Booting Python
How it plays
One lane matches. Find it.
A gate comes down the road with a pattern on top and a string over each lane. Steer Rex, the runner, into the lane whose string matches the whole pattern. Right lane: points and a longer streak. Wrong lane: you lose a life and the console shows why. On a phone, tap a lane or swipe.
What you learn
Six levels of regex
- Literals and any character
c.t - Character classes
[bcr]at - Repeats
go+l - Exact counts
\d{3} - Groups and either/or
(ha)+ - Real-world checks
#[0-9a-f]{6}
Why Python
Same rules, browser or desktop
The game rules live in one file, rules.py. In the browser it runs on Pyodide, which is Python compiled to WebAssembly. The download also has regex_runner.py, a pygame version that imports the same file. Run pip install pygame, then python regex_runner.py.