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

Substitution
Processing...

Code Generator

Language

Generated Code

import re regex = re.compile(r"(?:(?!<li>).)*<li>.*?<a href=\"([^\"]+)\".*?alt=\"On Contact: ([^\"]+)\".*?<p[^>]*>((?:(?!</p>).)+?)</p>.*?<p[^>]*>([^<]+)<(?:(?!<li>).)*", flags=re.MULTILINE | re.DOTALL) test_str = (" <li><p style=\"margin-bottom: 0in\"><a href=\"https://www.rt.com/shows/on-contact/550756-america-long-war-race/\">On\n" " Contact: Race and America's long war </a>\n" " </p>\n" " <p style=\"margin-bottom: 0in\"><a href=\"https://www.rt.com/shows/on-contact/550756-america-long-war-race/\">\n" " <font color=\"#000080\">\n" " <img src=\"rt.com-on_contact-220405-no_blurb_html_1dff87941f1c724a.jpg\" name=\"Image1\" alt=\"On Contact: Race and America's long war\" align=\"bottom\" width=\"280\" height=\"157\" border=\"1\"/>\n" " </font>\n" "</a>\n" "</p>\n" " <p style=\"margin-bottom: 0in\">On the show, Chris Hedges discusses\n" " America's inner and outer wars and its nexus with capitalism and\n" " empire with Professor of Social and Cultural Analysis and History at\n" " New York University Nikhil Pal Singh. The internal violence in the\n" " United... \n" " </p>\n" " <p style=\"margin-bottom: 0in\">Feb 27, 2022 10:36</p>\n" " <li><p style=\"margin-bottom: 0in\"><a href=\"https://www.rt.com/shows/on-contact/550319-george-washington-genocidal-colonist/\">\n" " <font color=\"#000080\">\n" " <img src=\"rt.com-on_contact-220405-no_blurb_html_198feb67032166ff.png\" name=\"Image3\" alt=\"On Contact: George Washington and the legacy of white supremacy\" align=\"bottom\" width=\"280\" height=\"157\" border=\"1\"/>\n" " </font>\n" "</a>\n" "</p>\n" " <p style=\"margin-bottom: 0in\"><strong><a href=\"https://www.rt.com/shows/on-contact/550319-george-washington-genocidal-colonist/\">On\n" " Contact: George Washington and the legacy of white supremacy </a></strong>\n" " </p>\n" " <p style=\"margin-bottom: 0in\">On the show, Chris Hedges discusses\n" " George Washington, the fallible human being and one of the principal\n" " architects of the United States, with author Nathaniel Philbrick. As\n" " America fractures into ideologically hostile camps, it colors how\n" " we... \n" " </p>\n" " <p style=\"margin-bottom: 0in\">Feb 25, 2022 09:09 \n" " </p>\n" " <li>[...]") subst = "$4\\t$2\\t$1\\t$3\\n" result = regex.sub(subst, test_str) if result: print(result)

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