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

r'
'
gm

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'^(((C|c)h(a|ă|ẵ|ẳ)n)|((L|l)(e|ẻ)))[\s\[]*(\d+\s?-?\s?\d*)[\s\]]*([\w\s]*)$' test_str = ("Chẵn 0-100 Bạch Đằng\n\n" "Chẵn [0] 2-204 Trần Thanh Mại\n" "Chẳn [0] 460-530 Kinh Dương Vương\n" "Chẳn [0] 460-532 Kinh Dương Vương\n\n" "Chẳn [100-262] Quốc lộ 13\n" "Chẵn 0 - 364 Phố Huế\n" "Chẵn 0 - 44 Tây Tựu\n" "Chẵn 0-100 Bạch Đằng\n" "Chẵn 0-100 Ngõ 124 Âu Cơ\n" "Chẵn 0-110 Đường Vành Đai\n" "Chẵn 0-110 Trâu Quỳ\n" "Chẵn 0-112 Đường Ô Chợ Dừa\n" "Chẵn 0-116 Đường số 8\n" "Chẵn 0-118 Bình Trị Đông\n" "Chẵn 0-128 Nguyễn Sơn\n\n" "Lẻ 1-13 đường Thạnh Lộc 29\n" "Lẻ 1-131 Đường số 4\n" "Lẻ 1-131 Hoàng Hoa Thám\n" "Lẻ 1-131 Kênh Mười Chín Tháng Năm\n" "Lẻ 1-131 Nguyễn Phúc Chu\n" "Lẻ 1-131 Trần Quang Cơ\n" "Lẻ 1-131 Trần Văn Kỷ\n" "Lẻ 1-133 Ấp Chiến Lược\n" "Lẻ 1-133 Bạch Đằng\n" "Lẻ 1-133 Khánh Hội\n" "Lẻ 1-133 Nguyễn Thiện Thuật\n" "Lẻ 1-134 Trần Hưng Đạo\n" "Lẻ 1-135 Đặng Chất\n" "Lẻ 1-135 Hoàng Hoa Thám\n" "Lẻ 1-135 Lý Phục Man\n" "Lẻ 1-135 Nguyễn Phong Sắc, Cầu Giấy, Hà Nội\n") matches = re.finditer(regex, test_str, 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