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"
"

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"(?P<delim>[^\w\n\"\'])(?P<space> ?)(?P<quote>[\"\'~]).*?(?P=quote)(?P=delim)" test_str = "~File Type~,~DV Dealer ID~,~Delegate Dealer ID~,~DMS Type~,~Stock Number~,~Vehicle Type~,~Vehicle Status~,~Inventory Date~,~Purchase Date~,~Sold Date~,~VIN~,~Year~,~Make~,~Model~,~Model Number~,~Odometer~,~Exterior Color~,~Exterior Color Code~,~Interior Color~,~Interior Color Code~,~Trim~,~Transmission~,~Cylinder~,~Weight~,~Description~,~Vehicle Style~,~Engine~,~Fuel Type~,~MPG~,~Standard Equipment~,~Factory Accessory Code~,~Factory Accessory Description~,~Factory Accessory Cost~,~Factory Accessory Retail~,~Accessory Code~,~Accessory Description~,~Accessory Cost~,~Accessory Retail~,~Accessory Invoice~,~Package Code~,~Location~,~Certification~,~Certification Number~,~Sales Code~,~Wholesale~,~Accounting Make~,~Open RO Number~,~License Fee~,~Category~,~Invoice~,~Cost Pack~,~Cost~,~Holdback~,~List Price~,~MSRP~,~Internet Price~,~VIN Explosion Year~,~VIN Explosion Make~,~VIN Explosion Model~,~VIN Explosion Trim~,~VIN Explosion Tran Type~,~VIN Explosion Fuel Type~,~VIN Explosion Chrome ID~,~VIN Explosion Engine Size~,~VIN Explosion GVW Range~,~Image Location URL~,~Video Location URL~,~Image Modified Date~" matches = re.search(regex, test_str) if matches: print ("Match was found at {start}-{end}: {match}".format(start = matches.start(), end = matches.end(), match = matches.group())) for groupNum in range(0, len(matches.groups())): groupNum = groupNum + 1 print ("Group {groupNum} found at {start}-{end}: {group}".format(groupNum = groupNum, start = matches.start(groupNum), end = matches.end(groupNum), group = matches.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