Regular Expressions 101

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Function

  • Match
  • Substitution
  • List
  • Unit Tests (24)

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An explanation of your regex will be automatically generated as you type.
  • 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
  • Match everything enclosed
    (?:...)
  • Capture everything enclosed
    (...)
  • 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

~
~

Unit Tests

given the string * * * * wednesday user /this/is/a/test.s… assert that regex does not match
given the string * * * * 7 user /this/is/a/test.sh > /som… assert that regex does not match
given the string * * * * wed user /this/is/a/test.sh > /s… assert that regex does match
given the string * * * * 6 user /this/is/a/test.sh > /som… assert that regex does match
given the string * * * * 0 user /this/is/a/test.sh > /som… assert that regex does match
given the string * * * 0 * user /this/is/a/test.sh > /som… assert that regex does not match
given the string * * * 13 * user /this/is/a/test.sh > /so… assert that regex does not match
given the string * * * 12 * user /this/is/a/test.sh > /so… assert that regex does match
given the string * * * 1 * user /this/is/a/test.sh > /som… assert that regex does match
given the string * * 32 * * user /this/is/a/test.sh > /so… assert that regex does not match
given the string * * 31 * * user /this/is/a/test.sh > /so… assert that regex does match
given the string * * 1 * * user /this/is/a/test.sh > /som… assert that regex does match
given the string * 24 * * * user /this/is/a/test.sh > /so… assert that regex does not match
given the string * 23 * * * user /this/is/a/test.sh > /so… assert that regex does match
given the string * 00 * * * user /this/is/a/test.sh > /so… assert that regex does match
given the string * 0 * * * user /this/is/a/test.sh > /som… assert that regex does match
given the string 15-30/5 * * * * user /this/is/a/test.sh … assert that regex does match
given the string 00,15,30,45 * * * * user /this/is/a/test… assert that regex does match
given the string */10 * * * * user /this/is/a/test.sh > /… assert that regex does match
given the string 60 * * * * user /this/is/a/test.sh > /so… assert that regex does not match
given the string 15 * * * * user /this/is/a/test.sh > /so… assert that regex does match
given the string * * * * user /this/is/a/test.sh > /some/… assert that regex does not match
given the string #* * * * * user /this/is/a/test.sh > /so… assert that regex does match
given the string * * * * * user /this/is/a/test.sh > /som… assert that regex does match

Code Generator

Language

Generated Code

$re = '~^\s*\#?\s*(?:(?:(?\'mins\'[0-5]?\d)(?:[-,](?&mins))*)|\*)(?:/\d{1,2})?\s+(?:(?:(?\'hours\'(?:2[0-3]|[01]?\d))(?:[-,](?&hours))*)|\*)(?:/\d{1,2})?\s+(?:(?:(?\'dmon\'(?:3[01]|[12]?\d))(?:[-,](?&dmon))*)|\*)(?:/\d{1,2})?\s+(?:(?:(?\'mon\'(?:1[0-2]|[1-9]))(?:[-,](?&mon))*)|\*)(?:/\d{1,2})?\s+(?:(?:(?\'dow\'(?:[0-6]|\b(?:mon|tue|wed|thu|fri|sat|sun)\b))(?:[-,](?&dow))*)|\*)(?:/\d{1,2})?\s+.+$~'; $str = ''; preg_match($re, $str, $matches, PREG_OFFSET_CAPTURE, 0); // Print the entire match result var_dump($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