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

Code Generator

Language

Generated Code

import re regex = re.compile(r".*", flags=re.DOTALL) test_str = ("$t = @(\n" " @(30, 29, 30, 29, 41),\n" " @(1, 1, 25, 30, 25, 30, 25, 25, 25, 25, 25, 25, 25, 25, 40, 1, 1),\n" " @(31, 34, 34, 20, 34, 28, 28, 23, 27, 31, 33, 34, 29, 24, 33, 32, 21, 34, 30, 21, 29, 22, 31, 23, 26, 32, 29, 32, 24, 27),\n" " @(26, 29, 22, 22, 31, 31, 27, 28, 32, 23, 33, 25, 31, 33, 34, 30, 23, 26, 21, 28, 32, 22, 30, 34, 26, 33, 20, 27, 33),\n" " @(20, 31, 20, 29, 29, 33, 34, 33, 20),\n" " @(25, 26, 34, 34, 41, 28, 32, 30, 34, 23, 26, 33, 30, 22, 30, 33, 24, 20, 27, 23, 30, 23, 34, 20, 23, 20, 33, 20, 28),\n" " @(34, 23, 31, 34, 34, 30, 29, 31, 29, 21, 25, 31, 30, 29, 29, 28, 21, 29, 33, 25, 24, 30),\n" " @(22, 31, 23, 23, 26, 21, 22, 20, 20, 28, 24, 28, 25, 31, 31, 26, 33, 31, 27, 29, 30, 30),\n" " @(26, 29, 25, 30, 32, 28, 26, 26, 33, 20, 21, 32, 28, 28, 20, 34, 34),\n" " @(34, 33, 29, 26, 34, 32, 27, 26, 22),\n" " @(30, 31, 23, 21, 30, 27, 32, 30, 34, 29, 21, 31, 31, 31, 32, 27, 30, 26, 21, 34, 29, 33, 24, 24, 32, 27, 32),\n" " @(25, 33, 33, 25, 24, 27, 34, 31, 29, 31, 27, 23)\n" ")\n\n" "$f = @(\n" " @(30),\n" " @(31, 29, 29, 28, 24, 23, 29, 29, 26, 27, 33, 20, 26, 26, 20, 30),\n" " @(29, 29, 29, 47, 30),\n" " @(23, 31, 29, 26, 30, 24, 29, 29, 25, 27, 24, 28, 22, 20, 34, 22, 32, 24, 33),\n" " @(23, 24, 25, 20, 24, 34, 28, 32, 22, 20, 24),\n" " @(24, 28, 21, 34, 34, 25, 24, 33, 23, 20, 32, 26, 29, 29, 25, 20, 30, 24, 23, 21, 27),\n" " @(26, 34, 21, 32, 32, 30, 32, 21, 34, 21, 34, 31, 23, 27, 26, 32),\n" " @(29, 24, 22, 27, 22, 25, 29, 26, 24, 24, 20, 25, 20, 20, 24, 20),\n" " @(23, 33, 22, 32, 30),\n" " @(28, 21, 22, 33, 22, 26, 30, 28, 26, 23, 31, 22, 31, 25, 27, 27, 25, 28),\n" " @(27, 23, 42, 23, 22, 28),\n" " @(25, 20, 30, 29, 32, 25, 22, 21, 31, 22, 23, 25, 22, 31, 23, 25, 33, 23)\n" ")\n\n" "\"Should be $true\"\n" "$t | % {\n" " [bool](.\\get-heatWave.ps1 @_)\n" "}\n\n" "\"Should be $false\"\n" "$f | % {\n" " [bool](.\\get-heatWave.ps1 @_)\n" "}") matches = regex.finditer(test_str) for match_num, match in enumerate(matches, start=1): print(f"Match {match_num} was found at {match.start()}-{match.end()}: {match.group()}") for group_num, group in enumerate(match.groups(), start=1): print(f"Group {group_num} found at {match.start(group_num)}-{match.end(group_num)}: {group}")

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 Python, please visit: https://docs.python.org/3/library/re.html