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
No Match

@"
"
gxmn

Test String

Code Generator

Language

Generated Code

# coding=utf8 # the above tag defines encoding for this document and is for Python 2.x compatibility import re regex = r""" \[\[( # link, and optional anchor (?<link>[^\|\#\]]+)?(\#(?<anchor>[^\|\]]+))? # display title (optional) (\|(?<title>[^|\]]+))? # tooltip (optional) (\|(?<tooltip>[^|\]]+))? )\]\] """ test_str = ("# Entry\n\n" "## Definition\n" "A published announcement made by a trusted [[Emitter]], detailing an event that occurred on their platform. \n\n\n" "## Specifications (3.0)\n" "#v3_0 \n\n" "A trustlist entry follows a basic structure, with parts being omitted during ingest, as these are filled by the receiving [[Directory]], responsible for the good tenure of this entry, and its correlation to existing data.\n\n" "As SocialGuard 1.0 to 3.0 tied its data to the [Discord](https://discord.com) [[Platform]], all data types are bound to that end.\n\n" "| Property | Type | Description | Requirement |\n" "| -------- | ---- | ----------- | ----------- |\n" "| `id` | Guid | ID of the entry. | Set by API |\n" "| `userId` | UInt64 | ID of the receiving [[User]]. | Required |\n" "| `entryAt` | DateTime | Date/Time at which the entry was emitted on the [[Directory]]. | Set by API |\n" "| `lastEscalated` | DateTime | Date/Time at which the entry was last escalated/edited. | Set by API |\n" "| `emitterId` | String | ID of the [[Emitter]] responsible for this Entry. | Set by API |\n" "| `emitter` | [[Emitter#Specifications (3.0)]] | Details of the [[Emitter]] responsible for this entry. | Set by API |\n" "| `escalationLevel` | [[#Range: Escalation level (3.0)]] | Escalation/Severity level of the events indicated by this entry. | Required |\n" "| `escalationNote` | String | Details of the event that led to this entry. | Required |\n\n" "### Range: Escalation level (3.0)\n" "This range defines the severity of an event leading to an entry. It is ranged by severity level and ordered from lowest to highest severity :\n\n" "1. **Suspicious**\n" " The [[User]] is marked as suspicious. Their behaviour should be monitored.\n" "2. **Untrusted**\n" " The [[User]] is marked as untrusted. It is advised to exercise caution when interacting with them.\n" "3. **Blacklisted**\n" " The [[User]] is deemed dangerous. Banning this user is greatly advised.\n\n\n") matches = re.finditer(regex, test_str, re.VERBOSE | re.MULTILINE) for matchNum, match in enumerate(matches, start=1): print ("Match {matchNum} was found at {start}-{end}: {match}".format(matchNum = matchNum, start = match.start(), end = match.end(), match = match.group())) for groupNum in range(0, len(match.groups())): groupNum = groupNum + 1 print ("Group {groupNum} found at {start}-{end}: {group}".format(groupNum = groupNum, start = match.start(groupNum), end = match.end(groupNum), group = match.group(groupNum))) # Note: for Python 2.7 compatibility, use ur"" to prefix the regex and u"" to prefix the test string and substitution.

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