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

@"
"
gmx

Test String

Code Generator

Language

Generated Code

$re = '/\s* ( (?<type>int(?:\s+long|\s+short)?|double(?:\s+long)?| long(?:\s+int|\s+double)?|short(?:\s+int)?|float|char) | (?<error>\w+|\w+\s*\,) ) \s+ (?: (?: (?: (?<error>int|double|float|char|long|short|[^,;a-zA-Z_].+?|[^,;]+?(?:\s+\w+?)+) | (?<id>[a-zA-Z_][a-zA-Z_0-9]*) ) (?:\s*\[\s*[1-9]\d*\s*\])* ) \s* (?:\,\s*|(?=\;)) )+ \s*\;\s*/mx'; $str = 'int abv, cde, doub1lel,ded, cto, int1; float ng23423, _ga45, astories; int af , f; int a, b, c;int short alt ; long double fgd [ 1 ], [1] , wef ; char _a[1], fi [ 3 ] [ 10] [ 4 ] ,g[1];int qw;'; preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0); // Print the entire match result var_dump($matches);

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