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

/
/
gms

Test String

Substitution

Processing...

Code Generator

Generated Code

$re = '/^(?!\t)(?:(FULL|SMALL)\W*)?([^\n]+)(.+?)(?=^(?!\t)\w+?|$(?!\n))/ms'; $str = ' Gahriel and Diana are standing in the living room. FULL: The living room has SOFA and a table. On the table have CUPCAKE and a NOTE at the bottom (or somewhere that doesn’t present the first time we see it.) Gahriel is walking to the kitchen calling out his mom. Gahriel Make yourself at home! Diana okay! Gahriel (calling out his mom) Mom? Where is she? SMALL- Diana inside the living room with Gabriel. She’s amazed with the picture on the wall related to his mother and young Gahriel. Diana ask Is this you and your mom? Gahriel (smiling) Haha, yup. That’s me. Diana (yelling and laughing so loud and keep talking) Diana Argh.. that’s so cute. Look at how chubby you are! '; $subst = "<div class=\"PANEL $1\">\n<div class=\"action\">$2</div></div>\n\n"; $result = preg_replace($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