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

/
/
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"(?i)(?:\w+\W+){0,9}?(?=.*(?:plot).*|.*(?:over).*)(?:\w+\W+){0,9}?(?=Charlie|Muir|Charlie Muir)\K(?:(?:Charlie|Muir|Charlie Muir)\s+)+" test_str = ("\n" "cHarlie muir charlie charlie was over the moon the the the the the tge the the the\n" "-the the the the the the the the the the the the the the the the the-\n\n" "over was the the the moon parker parker charlie muir charlie\n" "-the the the the the the the the the the the the the the the the the-\n\n" "Charlie muir charlie was near the plot\n" "-the the the the the the the the the the the the the the the the the-\n\n" "ChArlie was far away from the plot was far away from the\n" "-the the the the the the the the the the the the the the the the the-\n\n" "the plot was far away from CharLie\n" "-the the the the the the the the the the the the the the the the the-\n\n" "the plot was far away from CharLie muir charlie\n" "-the the the the the the the the the the the the the the the the the-\n\n\n\n" "the over was far away from CHarlie muir\n" "-the the the the the the the the the the the the the the the the the-\n\n" "Mr cHARLIE was bowled over test was bowled after the ball\n" "-the the the the the the the the the the the the the the the the the-\n\n" "over the test was bowled muIR\n" "-the the the the the the the the the the the the the the the the the-\n\n" "the plot the ball the slot it will plot the test was bowled MuiR\n" "-the the the the the the the the the the the the the the the the the-\n\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