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"(?i:(\[|\()(((donghua|anime).*)|((LOM|LotM|COI)( ?)(Vol|(Volume)?)( ?)([0-9\-&]*)( ?)(Chapter|Chap|(Ch)?)(.?)( ?)([0-9\-&]+|general|end)(\+?)([ \/]?privilege)?))(]|\)))", flags=re.MULTILINE) test_str = ("Examples that work\n" "[COI vol 5] Post title\n" "Post title (coi ch 890+)\n" "Post title (coi general)\n" "Post [Lotm something] title\n\n" "Examples that don't work\n" "[coi] with no vol/ch specification or the \"general\" keyword\n" "[idk lotm] lotm/coi must be at the start\n" "(Coi ch 8 cool) \" cool\" should be outside the brackets\n\n" "Lotm Tests\n" "[Lotm] Title here\n" "[LOM] Title here\n" "[Lotm ] Title here\n" "[LOM Vol 3] Lotm works with anything after it\n" "[Lom vol 3] Lotm works with anything after it\n" "[lotm random] stuff\n" "(lotm not closed fails\n\n" "COI tests\n" "[COI] fails\n" "[COI vol 3] Title here\n" "[COI ch850+] Title here\n" "[COI 231] Assumed this is the chapter #\n" "[coi352] a lazy person\n" "[COIvol3] Spacing Optional\n" "[COIch.3] Spacing Optional\n" "[coi231] lower case is fine\n" "[COIch293] hopefully no one does this in practice lol\n" "[COI vol 5 ch 894] should work\n" "[coi vol5 ch23]\n" "[coivol2ch.43] \n" "[coi chs 253-455] chapter range\n" "(coi vol 3&5) & character added\n" "[coi chs 231] \n" "[COI random] fails\n\n" "Anime/donghua tests (unadvertised)\n" "(donghua ep1) just added this, unadvertised though\n" "(anime trailer) unadvertised") 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