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"^(♪\h+[A-Za-z].*?(?:\R[A-Za-z].*?)?)♪?$", flags=re.MULTILINE) test_str = ("==============================\n" "BEFORE\n" "==============================\n" "400\n" "00:31:44,633 --> 00:31:45,716\n" "Come on.\n\n" "401\n" "00:31:59,940 --> 00:32:02,399\n" "Caleb used to do that\n" "when he ate.\n\n" "402\n" "00:32:03,902 --> 00:32:05,069\n" "Pull my hair like that.\n\n" "410\n" "00:32:46,653 --> 00:32:48,654\n" "♪ Saying</i>\n\n" "411\n" "00:32:48,738 --> 00:32:52,241\n" "♪ This is my message to you</i>\n\n" "412\n" "00:32:56,163 --> 00:32:57,538\n" "♪ Don't worry</i>\n\n" "636\n" "00:55:59,545 --> 00:56:02,296\n" "♪ You don't own me\n\n" "637\n" "00:56:02,798 --> 00:56:06,676\n" "♪ I'm not just\n" "one of your many toys\n\n" "638\n" "00:56:06,969 --> 00:56:09,929\n" "♪ You don't own me\n\n" "639\n" "00:56:10,347 --> 00:56:16,394\n" "♪ Don't say\n" "I can't go with other boys\n\n" "640\n" "00:56:16,728 --> 00:56:20,106\n" "♪ And don't tell me\n" "what to do\n\n" "641\n" "00:56:20,816 --> 00:56:24,026\n" "♪ Don't tell me what to say ♪\n\n" "642\n" "00:56:24,278 --> 00:56:27,822\n" "♪ And please,\n" "when I go out with you ♪\n\n" "643\n" "00:56:28,365 --> 00:56:31,742\n" "♪ Don't put me on display ♪\n\n" "644\n" "00:56:31,952 --> 00:56:36,080\n" "♪ 'Cause you don't own me ♪") subst = "$1 ♪" 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