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

r"
"
gm

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"\[([^\]]+)]\"?$" test_str = ("NO MATCHES:\n\n" " [q:Sacks and Snow: The Snow Child's Name] has run out of time. It asks to see you.\n\n" " \"My sleep is riddled with dreams, [q:Addressed As]. Dreams of bells and candles!\"\n\n" " The pirates must learn that [q:Pigmote Isle: Mastery] will fight back.\n\n" " [CHANGE_TERRAIN],EmpireofHands/airbase_half,EmpireofHands/airbase_burnt\n\n" " <b>MAYBE'S DAUGHTER</b>: Hello, Auntie.\\r\\n<br/>\\r\\n<b>PARABOLAN PANTHER<b/>: [Silence.]\\r\\n<br/>\\r\\n<b>MAYBE'S DAUGHTER</b>: Fair point. Let's keep it to ourselves for now.\\r\\n\n\n" " O[xxxxx] THRR [xxxxx] N KUTHE TH[xxxxxx].\n\n\n" "SHOULD MATCH:\n\n" " \"[q:Addressed As]. I know the way. Let me show you.\"\\n[The Exile is a First Officer.]\n\n" "(just the last part!)\n\n" " \"Herein are recorded certain details of a Voyage through [xxxxx] in the company of [xxxxxx], on [xxxxxx]....\" [Use this to increase your Pages]\n\n\n" "(how? it ends with quotes!)\n\n" " \"P drowns in PELIGIN, the colour of the deepest zee. [Someone has scrawled in the margin: BEYOND THE GATE THERE IS A SEA MORE SUNLESS]\"\n\n" "(trailing spaces)\n\n" " Decide later. [If you just want to get out to zee immediately, choose this. Opportunities to revisit your past will arrive later.]\n\n" " Really it's just him you want to understand. [This will certainly get you kicked off the island.]\n\n") matches = re.finditer(regex, test_str, 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