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""" (?'char'[A-F0-9]{4,7})\;(?'replace'.*)(?:\s{1}(?'replace'[A-F0-9]{4,7}))+(?=\s)+(?:\s{1}(?'replace'[A-F0-9]{4,7}))+(?=\s)+(?:\s{1}(?'replace'[A-F0-9]{4,7}))+\;\ (?'comment'.*)(?:\n)| (?'char'[A-F0-9]{4,7})\;(?'replace'.*)(?:\s{1}(?'replace'[A-F0-9]{4,7}))+(?=\s)+(?:\s{1}(?'replace'[A-F0-9]{4,7}))+\;\ (?'comment'.*)(?:\n)| (?'char'[A-F0-9]{4,7})\;(?:\s{1}(?'replace'[A-F0-9]{4,7}))+(?=\s)+(?:\s{1}(?'replace'[A-F0-9]{4,7}))+\;\ (?'comment'.*)(?:\n)| (?'char'[A-F0-9]{4,7})\;(?'replace'.*)\;\ (?'comment'.*)(?:\n)| (?'range_start'[A-F0-9]{4,7})\-(?'range_end'[A-F0-9]{4,7})(?:\;\ )(?'comment'.*)(?:\n)| (?'char'[A-F0-9]{4,7})(?:\;\ )(?'comment'.*)(?:\n)| (?'range_start'[A-F0-9]{4,7})\-(?'range_end'[A-F0-9]{4,7})(?:\n)| (?:^\ {3})(?'char'[A-F0-9]{4,7})(?:\n)| (?<appendix>(?'appendix_type'Start|End)\sTable\s(?'appendix_number'(\w).(?'appendix_order'(\d)))(?=\ -----\n)) """, flags=re.VERBOSE | re.MULTILINE) test_str = (" F001-AB12\n" " 0221\n" " 0234-024F\n" " 02AE-02AF\n" " 03AB; 03CB; Case map\n" " 03B0; 03C5 0308 0301; Case map\n" " 03C2; 03C3; Case map\n" " 03B0; 03C5 0308 0301 0A1B; Case map\n" " ----- Start Table A.1 -----\n" " 03D0; 03B2; Case map\n" " 03D1; 03B8; Case map\n" " ----- End Table A.1 -----\n" " 03D2; 03C5; Additional folding\n" " 03D3; 03CD; Additional folding\n" " 00DF; 0073 0073; Case map\n" " 037B-037D\n" " 037F-0383\n" " 038B\n" "Hoffman & Blanchet Standards Track [Page 89]\n" " \n" "RFC 3454 Preparation of Internationalized Strings December 2002\n" " 1806; ; Map to nothing\n" " 1806; ; Map to nothing\n" " 1806; ; Map to nothing\n" " 1806; ; Map to nothing\n" " F0000-FFFFD\n" " 100000-10FFFD\n" " F0000\n" " 013B; 013C; Case map\n" " 013D; 013E; Case map\n" " 0080-009F; [CONTROL CHARACTERS]\n" " 06DD; ARABIC END OF AYAH\n" " 070F; SYRIAC ABBREVIATION MARK\n" " 180E; MONGOLIAN VOWEL SEPARATOR\n" " 200C; ZERO WIDTH NON-JOINER\n" " 200D; ZERO WIDTH JOINER\n" " 2028; LINE SEPARATOR\n" " 2029; PARAGRAPH SEPARATOR\n" " 2060; WORD JOINER\n" " 2061; FUNCTION APPLICATION\n" " 2062; INVISIBLE TIMES\n" " 013F; 0140; Case map\n" " 0141; 0142; Case map\n" " 0143; 0144; Case map\n" " 0145; 0146; Case map\n" " 0147; 0148; Case map\n" " 0149; 02BC 006E; Case map\n" " 014A; 014B; Case map\n" " 014C; 014D; Case map\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