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"(?<FULL>^(?<PATH>(?:\/|\.|\.\.){0,2})(?<CAPTURE1>\/[^\/\s]+)?(?<CAPTURE2>\/[^\/\s]+)?(?<CAPTURE3>\/[^\/\s]+)?(?<CAPTURE4>\/[^\/\s]+)?(?<CAPTURE5>\/[^\/\s]+)?(?<CAPTURE6>\/[^\/\s]+)?(?<FILENAME>\/[^\/\s]+)$)", flags=re.IGNORECASE | re.MULTILINE) test_str = ("./src/index.js\n\n" "./src/index.js#Soda\n\n" "./src/index.js?soda=fries\n" "./src/index.js#soda?fries=hamburger\n" "./src/index.js#soda?fries=hamburger&bag+o=chips\n" "http://www.google.com/blugh/hello\n" "https://www.google.com:8080/src/ui/template-management/create-template/versioning/version.js\n" "http://localhost:8080/blugh/hello\n" "../MyPath\n" "This here is a normal sentence, though!\n" "./src/ui/{FILE}.js[x]?\n" "./src/ui/login.js\n" "./src/ui/logout.js\n\n" "./src/ui/{FILE}/{FILE}.js[x]?\n" "./src/ui/ad-hoc-messages/ad-hoc-messages.js\n" "./src/ui/editor/editor.jsx\n" "./src/ui/select-interaction/select-interaction.jsx\n" "./src/ui/template-management/template-management.js\n\n" "./src/ui/{DIR}/{FILE}/{FILE}.js[x]?\n" "./src/ui/ad-hoc-messages/send-ad-hoc-message/send-ad-hoc-message.js\n" "./src/ui/admin-console/Department-management/Department-management.js\n" "./src/ui/admin-console/tag-management/tag-management.js\n" "./src/ui/template-management/create-template/create-template.js\n" "./src/ui/template-management/create-template/versioning/version.js\n\n" "./src/ui/{DIR}/{FILE}.js[x]?\n" "./src/ui/shared/select-template-to-send.js\n" " \n" "/select-interaction\n" "/template-management\n" "/template-management/create-template\n" "/template-management/edit-template\n" "/ad-hoc-messages\n" "/ad-hoc-messages/send-ad-hoc-mail\n" "/admin-console/category-management\n" "/admin-console/tag-management\n" "/Logout") 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