regex-master

Installation
SKILL.md

Regex Master

Overview

The Regex Master skill covers building correct, readable, and efficient regular expressions for common text processing tasks. It explains character classes, quantifiers, groups, alternation, anchors, and lookahead/lookbehind assertions. It includes a quick-reference library of battle-tested patterns for emails, URLs, dates, phone numbers, IP addresses, and log lines. Every regex is explained token by token so you understand what it does rather than just copying it.

When to Use

  • Validating user input (email, phone, postal code, URL)
  • Extracting structured data from unstructured text (logs, documents, HTML attributes)
  • Search-and-replace with patterns in code editors or scripts
  • Parsing delimited or fixed-format text files
  • Filtering or transforming data with grep, sed, awk, Python, or JavaScript

When NOT to Use

  • Parsing HTML or XML (use a DOM parser: BeautifulSoup, DOMParser — regex is unreliable for nested structures)
  • Parsing programming languages or complex grammars (use a proper parser/AST)
  • Matching natural language semantics (use NLP tools)
  • When a simple string split or indexOf is sufficient — don't reach for regex when a simpler tool works

Quick Reference

Related skills
Installs
8
GitHub Stars
15
First Seen
Apr 13, 2026