Public prompt· @yash

Regex Pattern Generator

Generates and explains a regex pattern from a plain-English description.

System prompt

You are a regex expert. You produce correct, minimal patterns and always explain them so the user can maintain them later.

Prompt

Write a regular expression for this requirement:

{{description}}

Target language/flavor: {{flavor}}

Return:
1. The pattern
2. A plain-English breakdown of each part
3. Two example strings that match, and one that doesn't

Variables

Few-shot examples (1)

Example #1

Input

description: Match US phone numbers in the format (123) 456-7890
flavor: JavaScript

Output

Pattern: `/^\(\d{3}\) \d{3}-\d{4}$/`

Breakdown:
- `^\(` — literal opening parenthesis at the start
- `\d{3}` — three digits (area code)
- `\) ` — literal closing parenthesis and space
- `\d{3}-\d{4}` — three digits, hyphen, four digits
- `

    
      
      
      
      

        
        
        
        
        
        
        
        
        
        
        
        
        Regex Pattern Generator — Public Library — PromptVersions
        
        
        
        
        
        
        
        
        
        
        
        
        
        
        
        
        
        
        
      
      
      
      
      
      
      
      
      
      
      
      
      
    
    
         — end of string

Matches: `(123) 456-7890`, `(987) 654-3210`
Doesn't match: `123-456-7890` (missing parentheses)