Regex Cheatsheet - Regular Expression Quick Reference
Quick reference for regular expression patterns. Character classes, quantifiers, anchors, and common patterns.
Positive Lookahead (?=abc)
AssertionMatches position followed by specified expression (zero-width)
Pattern
(?=abc)Syntax
Explanation
Positive lookahead doesn't consume characters; it only checks ahead.
Examples
\w+(?=ing)Match word stem before "ing"
Matches: run (in running)
\d+(?=\.\d{2})Match integer before two decimals
Matches: 100 (in 100.00)
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