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

/
/
gx

Test String

Substitution

Processing...

Code Generator

Language

Generated Code

$re = '/# Look for `Wild Draw Four` or simply `Wild` # `W` stored in \1, `D` and `F` stored in \2 and \3, respectively (W)I\ LD(?:\ (D)raw\ (F)our)? | # Look for `Draw Two` or `Draw Four` # `D` stored in \4, `T` or `F` stored in \5 (D)raw\ (?|(T)wo|(F)our) | # Look for the color and then the card type or number value # `R`, `G`, `Y`, and `B` stored in \6 # `S`, `R` or number value stored in \7 (?:(?|(R)ed|(G)reen|(Y)ellow|(B)lue)\ (?|(S)kip |(R)everse |(\d) ) )/x'; $str = 'GIVEN: Green 4 Green 4 Green 7 WI LD Green 9 Green 9 Red 3 Red 3 Red 4 WI LD Draw Four Red 5 Red Reverse Yellow 0 Yellow Skip Green 8 WI LD Draw Four Green 4 Green Reverse Yellow 6 WI LD WI LD Draw Four WI LD Green 6 WI LD Draw Four Green 6 DESIRED: G4 G4 G7 W G9 G9 R3 R3 R4 WDF R5 RR Y0 YS G8 WDF G4 GR Y6 W WDF W G6 WDF G6 '; $subst = "\1\2\3\4\5\6\7"; $result = preg_replace($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