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""" # Chunk or note time. (?<= \| ) (?: \s+) (\() ([0-2][0-9]) (:) ([0-5][0-9]) (\)) (?= \s+ \|) | # Revision title. (?<= \s \| \s) (\(.+\s\#\d+\)) (?= \s+ \|) | # Chunk title. (?<= \| \s [0-2][0-9] : [0-5][0-9] - [0-2][0-9] : [0-5][0-9] \s \| \s ) (?! \[ | \s* \| ) (?:\s*)? (.+?) (?= \s+ \|) | # Chunk note. (?<= \s \| \s ) (?! -{2} ) (- .+?) (?= \s+ \|) """, flags=re.MULTILINE | re.VERBOSE) test_str = ("[^\\S\\n] (?:\\s*\\r\\n|\\s*\\r|\\s*\\n)\n\n\n" "# Time block\n\n" "| Time | Block |\n" "| ----------: | :---------------- |\n" "| (00:00) | (Revision #1) |\n" "| | |\n" "| 00:00-00:00 | Chunk |\n" "| | - Note w/ details |\n" "| 00:00-00:00 | Some meeting |\n" "| 11:00-13:00 | Chunk |\n" "| 13:00 | - Note w/ details |\n" "| | |\n" "| (00:00) | (Revision #1) |\n" "| 00:00-00:00 | Chunk |\n" "| | - Note w/ details |\n\n" "## Time Tracking\n\n" "| Tracker | Task | Backlog |\n" "| ----------: | :---------------------------------- | :------------ |\n" "| 08:04-08:53 | [x] * Task for deep work block (#1) | [[wiki.link]] |\n" "| 09:07-09:56 | | Don't match |\n" "| 98m | | |\n" "| | | |\n" "| 00:00-00:00 | Can Match | |\n" "| | Don't Match | |\n" "| 00:00-00:00 | | Don't match |\n\n" "Group 1: `(` for time\n" "Group 2: `00` hour (for chunk)\n" "Group 3: `:` (for chunk)\n" "Group 4: `00` minute (for chunk)\n" "Group 5: `)` for time\n" "Group 6: `(Revision #1)`\n" "Group 7: `Chunk`or `Some meeting`\n" "Group 8: `- Note w/ details`\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