Emacs Regex vs Regex in Python, JavaScript, Java

By Xah Lee. Date: . Last updated: .

Emacs regular expression is different from the regular expression in JavaScript, Python, Ruby, Perl etc.

Here are practical major differences.

Regular Expression
JavaScript,
Python,
Perl,
Java Etc
emacs lisp
(may not be exactly equivalent)
Capture"(capture)""\\(capture\\)"
digit"\d""[0-9]" or "[[:digit:]]"
word"\w""[_A-Za-z0-9]" or "[[:word:]]"
whitespace"\s""[ \n\t]" or "[[:space:]]"

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