Regular Expressions 101

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An explanation of your regex will be automatically generated as you type.
Detailed match information will be displayed here automatically.
  • All Tokens
  • Common Tokens
  • General Tokens
  • Anchors
  • Meta Sequences
  • Quantifiers
  • Group Constructs
  • Character Classes
  • Flags/Modifiers
  • Substitution
  • A single character of: a, b or c
    [abc]
  • A character except: a, b or c
    [^abc]
  • A character in the range: a-z
    [a-z]
  • A character not in the range: a-z
    [^a-z]
  • A character in the range: a-z or A-Z
    [a-zA-Z]
  • Any single character
    .
  • Alternate - match either a or b
    a|b
  • Any whitespace character
    \s
  • Any non-whitespace character
    \S
  • Any digit
    \d
  • Any non-digit
    \D
  • Any word character
    \w
  • Any non-word character
    \W
  • Non-capturing group
    (?:...)
  • Capturing group
    (...)
  • Zero or one of a
    a?
  • Zero or more of a
    a*
  • One or more of a
    a+
  • Exactly 3 of a
    a{3}
  • 3 or more of a
    a{3,}
  • Between 3 and 6 of a
    a{3,6}
  • Start of string
    ^
  • End of string
    $
  • A word boundary
    \b
  • Non-word boundary
    \B

Regular Expression
No Match

/
/
gm

Test String

Substitution

Processing...

Code Generator

Language

Generated Code

$re = '/(\w+:\/\/[\w\.]+?\/([\w\.]+?)\/([\w\.]+?))\s/m'; $str = '1. https://github.com/ymcatwincities/openy_block_modal - Implements a simple block with a body and title that will be used to display modal windows. 1. https://github.com/ymcatwincities/openy_memberships - Membership Framework for OpenY and Drupal. 1. https://github.com/ymcatwincities/openy_prgf_sidebar_menu - SideBar menu for referencing menu blocks and using in SideBars across different pages. 1. https://packagist.org/packages/openy/openy_loc_finder - Extended Location Finder 1. https://github.com/Open-Y-subprojects/reqclique_gxp_sync - Reqclique Group Exercise Sync 1. https://github.com/open-y-subprojects/virtual_y_signaling_server - Signalling server for Virtual Y'; $subst = "[$2/$3]($1) "; $result = preg_replace($re, $subst, $str); echo "The result of the substitution is ".$result;

Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php