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
No Match

/
/
xgJm

Test String

Code Generator

Language

Generated Code

# coding=utf8 # the above tag defines encoding for this document and is for Python 2.x compatibility import re regex = 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)) """ 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 = re.finditer(regex, test_str, re.VERBOSE | re.MULTILINE) for matchNum, match in enumerate(matches, start=1): print ("Match {matchNum} was found at {start}-{end}: {match}".format(matchNum = matchNum, start = match.start(), end = match.end(), match = match.group())) for groupNum in range(0, len(match.groups())): groupNum = groupNum + 1 print ("Group {groupNum} found at {start}-{end}: {group}".format(groupNum = groupNum, start = match.start(groupNum), end = match.end(groupNum), group = match.group(groupNum))) # Note: for Python 2.7 compatibility, use ur"" to prefix the regex and u"" to prefix the test string and substitution.

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