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""" (?|(?:\G(?!\A)(?<=\|)|^\|\h*\[x\]\h*\|)\h*\K([^|\n]+)(?<=\S)\h*\||\[x]\h*\K([^|\s!]+(?:\h*[^|\s]+)*))| (?|(?:\G(?!\A)\||^\|\h*\[x]\h*!\h*\|)\h*\K([^|\n]+)(?<=\S)\h*|\[x]\h*!\h*\K([^|\s]+(?:\h*[^|\s]+)*)) """, flags=re.MULTILINE | re.VERBOSE) test_str = ("Test cases where it should match.\n" "- [x] Example task. | Task ends. [x] Another task.\n" "- [x] ! Example task. | This ends. [x] ! Another task.\n" "- [x] Example task! | Task ends. [x] Another task!\n" "- [x] ! Example task! | This ends. [x] ! Another task!\n\n" "This is a sentence. [x] Task is here.\n" "Other text. Another [x] ! Task is here.\n\n" "Must not match in the table.\n" "| | Task name | Plan | Actual | File |\n" "| :---- | :-------------| :---------: | :---------: | :------------: |\n" "| [x] | Task example. | 08:00-08:45 | 08:00-09:00 | [[task-one]] |\n" "| [x] ! | Task example. | 08:00-08:45 | 08:00-09:00 | [[task-one]] |\n\n" "Groups expected:\n" "$1: all text after [x]\n" "$2: all text after [x] !\n\n" "Regex for each group:\n" "$1: [^\\|\\s]\\s*\\[x\\]\\s*\\K[^!|\\n]*\n" "$2: [^\\|\\s]\\s*\\[x\\]\\s*\\!\\s*\\K[^|\\n]*\n\n" "With the not-capturing group applied:\n" "$1: (?:[^\\|\\s]\\s*\\[x\\]\\s*\\K[^!|\\n]*)\n" "$2: (?:[^\\|\\s]\\s*\\[x\\]\\s*\\!\\s*\\K[^|\\n]*)\n\n" "The combined expression:\n" "(?:[^\\|\\s]\\s*\\[x\\]\\s*\\K([^!|\\n]*))|(?:[^\\|\\s]\\s*\\[x\\]\\s*\\!\\s*\\K([^|\\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