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"(?:[^\p{Script=Latin}\s\w;:.,\-[\](){}'\"+\/=<>])\B|(?:(?:[\p{Script=Latin}]|[^\s\w;:.,\-[\](){}'\"+\/=<>]){2,}(?:(?:[\p{Script=Latin}]|[^\s\w+.,–:;\/\\=<>])?(?:[\p{Script=Latin}]|[^\s\w;\-:.,\[\](){}'\"+\/\\=<>]))*)|(?:(?:[0-9\p{Script=Latin}]|[^\s\w;:.,[\](){}\-'\"+\/\\=<>])(?:(?:[0-9\p{Script=Latin}]|[^\s\w+\-:;\/\\=<>])?(?:[0-9\p{Script=Latin}]|[^\s\w;:.,\-[\](){}'\"+\/\\=<>]))*)", flags=re.MULTILINE | re.UNICODE | re.IGNORECASE) test_str = ("Bão Yagi (được Việt Nam định danh là bão số 3, được phía Philippines đặt tên bão Enteng - tiếng Anh: Severe Tropical Storm Enteng , nguyên văn 'Bão nhiệt đới dữ dội Enteng')\n\n" "Some legal \"[d]ocuments\" contain corrected spel[l]ing, gram(m)ar, or simple typos; and lots of references[1]. By Extension, I included curl{e}y brackets, but not tag brack<e>ts, which are not seenin modern legal documents.\n\n" "These.are.properly.separated.even.U.S.A., and multiple punctuations are properly ignored.\n\n" "A. Multiple\n" "B. Choices\n\n" "-ABC-DEF-\n" "-A-B-C-D-\n" "-1-2-3-4-\n" "-test-\n\n" ".ABC.DEF.\n" ".AB.CD.EF.D.\n" ".A.B.C.D.E.\n" ".123.456.789.\n" ".12.34.56.78.\n" ".1.2.3.4.\n\n" "cod3 var1aBl3s\n" "test.U.S.A.test\n\n" "We'd want hyphenated words in cases when large words are broken for wrapping in tight column news papers/megazines, while we can still properly separate numbers such as \"30-35 pages\".\n\n" "Non-Latin character are separated per character:\n" "出典: フリー百科事典『ウィキペディア（Wikipedia）』\n" "ウィキペディアには現在この名前の項目はありません。\n\n" "Acceptable failed cases:\n\n" "- [E]xpected: \"[\" is considered external \"wrapper/enclosure\", while the internal \"wrappers\" are included so that they can be further processed/removed in the future.\n\n" "- test.U.S.A.test: this happens when no space trailing textContents of a block-level elemetn in HTML files.\n\n" "- 『ウィキペディア（Wikipedia）』: mixed languages\n\n" "- CamelCasing s not separated, but can be easily separated in \"post-processing step, even though _snake_casing_ works fine by happenstance.\n\n" "-cod3 var1aBl3s: mixing letters and numbers. It's not intentional, but not a big deal when the side-effect is new word is always started with a number.") 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