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

/
/
gi

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"(\[(?<first>icode|quote|code)[^\]]*?\](?:[\s]*?.)*?[\s]*?\[\/(?:\k<first>)\])" test_str = ("[quote]Id in voluptatem [U]odit itaque[/U] ea. Qui eum [URL='http://#']fugiat[/URL] doloribus dicta nisi. [icode]Exercitationem sit error maxime aperiam quaerat hic deleniti quidem[/icode]. Totam laudantium aut quia. \"Sint ut ut vel ratione,\" Qui porro eaque enim fugit.\n" "[/quote]\n\n" "Quam consequatur consequatur voluptate molestiae explicabo [icode]qui consectetur[/ICODE], \"Voluptatem saepe [b]ex adipisci aut est rem[/b].\" Numquam a cupiditate non officiis sed aspernatur.\n\n" "[quote=\"Lorem Ipsum, post: 12345, member: 123\"]Aut deleniti nihil sit. Saepe dolorem blanditiis nemo. Ab et cumque nesciunt. Quos velit vel nam porro.[/quote]\n\n" "[spoiler=\"Name\"]Unde et eius tempore consequatur. \"Vitae est ut et,\" est numquam.\"\"[/spoiler]\n\n" "Quo <span style=\"color: #24c4f9\"><b>suscipit</b></span> sequi id ratione \"doloribus omnis\".\n\n" "<span style=\"font-family: 'Lucida Console'\"><span style=\"font-size: 18px\">Lorem ipsum dolor sit amet, consectetur adipiscing elit.\n" "\"\n" "Maecenas sed nibh ac neque semper finibus.\n" "Saepe dolorem blanditiis nemo.\n" "\"\n" "</b></span>\n\n" "[CODE=html]\n\n" "Vivamus hendrerit augue \"volutpat\", consequat risus sed, dignissim orci.\n\n" "Fusce sed pellentesque ipsum. Suspendisse nisi odio, gravida sed leo ut, tristique posuere felis.\n" "[/CODE]\n\n" "Ut tempor vestibulum viverra. Vivamus imperdiet fringilla est fermentum facilisis. Quisque nec massa sit amet augue eleifend condimentum at nec arcu.\n\n" "[CENTER][B]Quam consequa[/B] \"tur c[I]onse[/I]quatur\". Eum molestias \"et\" doloribus et rem dolorem vero qui.[/CENTER]") matches = re.finditer(regex, test_str, re.IGNORECASE) 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