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]{2,})(?!.*[&@])(.*?)([,{])\n", flags=re.MULTILINE) test_str = ("#term-header {\n" " padding: 20px 0 17px;\n" " margin: 0 10px 30px;\n" " &::before,\n" " &::after {\n" " margin-left: -11px;\n" " border-width: 12px 10.5px 0 10.5px;\n" " }\n" " &::before {\n" " bottom: -12px;\n" " }\n" " &::after {\n" " bottom: -10px;\n" " }\n" " h1 {\n" " font-size: 20px;\n" " span {\n" " font-size: 27px;\n" " }\n" " }\n" " dl {\n" " margin: 20px 0 0;\n" " dt {\n" " width: 100px;\n" " }\n" " dd {\n" " font-size: 11px;\n" " }\n" " }\n" "}\n\n" ".slick-next,\n" ".slick-prev {\n" " width: 35px;\n" " height: 35px;\n" "}\n" ".slick-prev {\n" " left: 5px;\n" " transform: translate3d(-30px, 0, 0);\n" " &::after {\n" " left: 14px;\n" " }\n" "}\n" ".slick-next {\n" " right: 5px;\n" " transform: translate3d(30px, 0, 0);\n" " &::after {\n" " right: 14px;\n" " }\n" "}\n" ".ready.inview {\n" " .slick-prev {\n" " &.slick-disabled {\n" " transform: translate3d(-30px, 0, 0);\n" " }\n" " }\n" " .slick-next {\n" " &.slick-disabled {\n" " transform: translate3d(30px, 0, 0);\n" " }\n" " }\n" "}\n\n" ".wp-editor {\n" " font-family: var(--fontFamily);\n" " font-size: var(--fontSize);\n" " line-height: var(--lineHeight);\n" " & h3,\n" " & h4,\n" " & p {\n" " margin: var(--wpEditorMargin) 0;\n" " overflow: hidden;\n" " &:first-child {\n" " margin-top: 0;\n" " }\n" " &:last-child {\n" " margin-bottom: 0;\n" " }\n" " }\n" " & h3 {\n" " font-size: 14px;\n" " }\n" " & h4 {\n" " font-size: 13px;\n" " }\n" " & a {\n" " color: var(--linkColor);\n" " text-decoration: underline;\n" " &:hover {\n" " text-decoration: none;\n" " }\n" " }\n" " & img {\n" " max-width: 100%;\n" " height: auto;\n" " }\n" " & blockquote {\n" " padding-left: 15px;\n" " margin: var(--wpEditorMargin) 0;\n" " font-weight: bold;\n" " border-left: 5px solid var(--borderColor);\n" " @media (--viewport-medium) {\n" " padding-left: 35px;\n" " }\n" " }\n" "}") 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