Coding
Build and understand a regex
Produces a regex with a piece-by-piece breakdown and its failure cases.
Prompt
I need a regular expression that matches: {{requirement}}
Should match:
{{should_match}}
Should NOT match:
{{should_not_match}}
Give me:
1. The regex
2. A breakdown of every component and what it does
3. Test results against each of my examples above
4. Two inputs that would break it unexpectedly
5. A plain-code alternative if regex is the wrong tool here
Flavour: {{language}}Fill these in
Replace each highlighted variable before sending. Leaving them in place is the most common reason these prompts under-perform.
| Variable | What to put | Example |
|---|---|---|
{{requirement}} | What to match | Nepali mobile numbers |
{{should_match}} | Positive examples | 9841234567, +9779841234567 |
{{should_not_match}} | Negative examples | 1234567890 |
{{language}} | Regex flavour | JavaScript |
Tips for better output
- Point 5 matters: regex is often the wrong answer, and a good model will say so.
- Always test the two 'breaking' inputs it gives you.