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

/
/
gmi

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"(.*\n\n((^>+\s{1}.*$)+\n?)+)" test_str = ("and again\n\n" "2016-05-06 14:27 GMT+03:00 serg radzishevsky :\n\n" "> ok cool comment #2\n" ">\n" "> 2016-05-06 14:24 GMT+03:00 Sergey Radzishevsky :\n" ">\n" ">> first comment\n" ">>\n" ">> *Lorem Ipsum* is simply dummy text of the printing and typesetting\n" ">> industry. Lorem Ipsum has been the industry's standard dummy text ever\n" ">> since the 1500s, when an unknown printer took a galley of type and\n" ">> scrambled it to make a type specimen book. It has survived not only five\n" ">> centuries, but also the leap into electronic typesetting, remaining\n" ">> essentially unchanged. It was popularised in the 1960s with the release of\n" ">> Letraset sheets containing Lorem Ipsum passages, and more recently with\n" ">> desktop publishing software like Aldus PageMaker including versions of\n" ">> Lorem Ipsum\n" ">>\n" ">> --\n" ">> *Sergey Radzishevsky*\n" ">> \n" ">> [image: Facebook page] [image:\n" ">> Twitter account] [image: Dribbble\n" ">> account] [image: Github repository]\n" ">> [image: Linkedin account]\n" ">> \n" ">>\n" ">> *Skype*: * radzserg*\n" ">>\n" ">>\n" ">\n" ">\n" "> --\n" "> Best Regards\n" ">\n" "> Radzishevsky Sergey\n" ">\n" "> *Skype: radzserg*\n" ">\n") matches = re.finditer(regex, test_str, re.MULTILINE | re.IGNORECASE) 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