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
Processing...

Test String

Substitution
Processing...

Code Generator

Language

Generated Code

$re = '/^(?:.*?\bRationale-|Normal|List Paragraph\t(?:\d+\)[ \t]*)?)[ \t]*/m'; $str = 'List Paragraph 36) Rationale-1 - Details on the context: List Paragraph 37) None. Normal List Paragraph 38) 2 - Statement complements: List Paragraph 39) Blablablabla List Paragraph (1) Blablablabla List Paragraph (2) Blablablabla List Paragraph (3) Blablablabla List Paragraph (4) Blablablabla List Paragraph (5) Blablablabla List Paragraph (6) Blablablabla List Paragraph (7) Blablablabla Normal List Paragraph 40) Blablablabla Normal List Paragraph 41) 3 - Statement justification: List Paragraph 42) Blablablabla Normal List Paragraph 43) Blablablabla List Paragraph 44) Blablablabla List Paragraph 45) Blablablabla List Paragraph 46) Attached Files: Rationale- Normal'; $subst = ""; $result = preg_replace($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