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"^((?:.+?, .+?;)*?(?:[^;\s]+?, .+?)\.)([^;]+?\.).*$", flags=re.MULTILINE) test_str = ("DI MAIO, P. The Missing Pragmatic Link in the Semantic Web. Business Intelligence Advisory Service Executive Update. v. 8, n. 7, 2008.\n\n" "ECO, U. Lector in Fabula: la cooperación interpretativa en el texto narrativo. Barcelona: Lumen, 1987\n\n" "ECO, U. O conceito de texto. São Paulo: T. A. Q. /EDUSP, 1984.\n\n" "ECO, U. Obra aberta: forma e indeterminação nas poéticas contemporâneas. São Paulo: Perspectiva, 1988.\n\n" "ECO, U. Os limites da interpretação. São Paulo: Pioneira, 2000.\n\n" "EDMONDS, B. The Pragmatic Roots of Context. In: PROC. OF THE 2ND INTERNATIONAL AND INTERDISCIPLINARY CONFERENCE ON MODELING AND USING CONTEXT. Berlin; Heidelberg; New York, v. 1688, 1999. Anais… v. 1688, p. 119-132, 1999.\n\n" "BERNERS-LEE, T. Semantic Web Concepts. 2005a. Disponível em: http://www.w3.org/2005/Talks/0517-boit-tbl. Acesso em: 25 set. 2014\n\n" "BERNERS-LEE, T. Web for real people. 2005b. Disponível em . Acesso em: 25 set. 2014.\n\n" "BERNERS-LEE, T.; CAILLIAU, R. WorldWideWeb: Proposal for a HyperText Project. 1990. Disponível em: < http://www.w3.org/Proposal.html >. Acesso em: 13 out. 2014.\n\n" "BERNERS-LEE, T.; HENDLER, J.; LASSILA, O. The semantic web: a new form of web content that is meaningful to computers will unleash a revolution of new possibilities. New York: Scientific American, 2001. Disponível em: http://www.sciam.com/2001/050lissue/0501berners-lee.html. Acesso em: 13 out. 2014.") 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