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]
  • Character class intersection
    [\w&&[^\d]]
  • 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

Generated Code

import re regex = re.compile(r"(### EXAMPLE ([0-9|[0-9]+))\n(```\n(```|```ps|```posh|```powershell)\n```\n)\n([\s\S]*?)\\`\\`\\`(\n\n|\n)([\s\S]*|\n)", flags=re.MULTILINE) test_str = ("### EXAMPLE 123\n" "```\n" "```powershell\n" "```\n\n" "$powershellVersion = '6 and lower'\n" "$description = 'custom code fencing example WITH markdown description'\n" "$names | Foreach-Object {} {\n" " write-host 'indentation is respected'\n" " Write-Host 'enormously long lines should not get cut off by our PlatyPS friends, ftw'\n" "}\n\n" "$emptyNewlinesInCode = $True\n" "\\`\\`\\`\n\n" "The description would continue after first closing code fence.\n\n" "This solution:\n\n" "- respects indentation\n" "- will treat description as markdown\n" "- seems close to what comes natural\n\n" "With this solution, the description itself could even contain code blocks:\n\n" "\\`\\`\\`js\n" "$var = docusaurus.New($config);\n" "\\`\\`\\`\n\n" "Pretty cool and the console becomes more readable too IMO, at least\n" "you now see where the code ends and the explanation begins\n\n" "\\`\\`\\`\n" "$unMonicked = \"should stay unmonicked, in other words powershell should not be added\"\n" " $indentationRespected = $True\n" "$theBadNews - \"that PlatyPS seems to cut off this line if a .\n" "is detected, wtf\"\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