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]
  • Character class intersection
    [\w&&[^\d]]
  • 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"^(?::\w*:|(?:\ud83c[\udf00-\udfff])|(?:\ud83d[\udc00-\ude4f\ude80-\udeff])|[\u2600-\u2B55])\s(?<type>[a-zA-Z-,\/]+)(?:\((?<scope>.*)\))?!?:\s(?<subject>(?:(?!#).)*(?:(?!\s).))(?:\s\(?(?<ticket>#\d*)\)?)?$", flags=re.MULTILINE) test_str = ("// Not Matched\n" "chore(scope): test\n\n" "hello :test: test\n\n" ":start:test: test\n\n" "// Matched\n\n" ":hello: test: test\n\n" ":start: chore(scope): test\n\n" ":start: chore(scope): test #123\n\n" ":memo: docs: update README.md\n\n" ":start: chore(scope): i have a word #123\n\n\n" ":package: feat(parser-opts): extract parser-opts packages\n\n\n" ":sparkles: feat(changelog): 添加中文标题\n\n" ":sparkles: feat(changelog): add chinese title\n\n" "✨ feat(unicode): add unicode support\n\n" "😌 test(only): add unicode support\n\n" ":sparkles: feat: hello world (#100)\n\n" ":green_heart: fix-ci(ci/cd): added release rules for all cz-emojis\n\n" ":green_heart: ci/cd(config): changed config for cz-emojis\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