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"^((CAPR?I?\s?SUN\b)|(CAPRI\b)|(C\W?S\b)|(JUICES?\b)|(STRAWBERRY\b))" test_str = ("C/S ARIETY PACK 40CT CS C/S\n" "CAPRI SN SPR V FRTPNCH 10PK\n" "CAPRI SN SPR V JCE APPLE 10PK\n" "CAPRI SN SPR V JCE BERRY 10PK\n" "CAPRI STRAWNANA MINIONS CAPRI\n" "CAPRI SUN100% JUICE APPLE SPL\n" "CAPRI SUN 100% JUICE BERRY BRE\n" "CAPRI SUN 100% JUICE FRUIT DIV\n" "CAPRI SUN 100% JUICE GRAPE TID\n" "CAPRI SUN 40CT 100% JUICE VAR\n" "CAPRI SUN 40CT ROARING WATERS\n" "CAPRI SUN 40CT VARIETY PACK\n" "CAPRI SUN COOL 40 CT\n" "CAPRI SUN FRT PNCH SPOUTED PCH\n" "CAPRI SUN FRT PUNCH 30CT\n" "CAPRI SUN FRUIT PUNCH\n" "CAPRI SUN FRUIT/VEGGIE APPLE SWEET POTATO SMASH 10CT\n" "CAPRI SUN FRUIT/VEGGIE PUNCH CARROT CRAZE 10PK\n" "CAPRI SUN GRAPE\n" "CAPRI SUN KWI SPOUTED PCH\n" "CAPRI SUN LEMONADE\n" "CAPRI SUN MOUNTAIN COOLER\n" "CAPRI SUN ORANGE\n" "CAPRI SUN ORGANIC APPLE 10PK\n" "CAPRI SUN ORGANIC FRUIT PUNCH 10PK\n" "CAPRI SUN ORGANIC GRAPE 10PK\n" "CAPRI SUN ORGANIC TROPICAL PUNCH 10PK\n" "CAPRI SUN PACIFIC COOLER\n" "CAPRI SUN PACIFIC COOLER 30/6 OZ\n" "CAPRI SUN RED BERRY\n" "CAPRI SUN ROARIN WATER BERRY\n" "CAPRI SUN ROARIN WATER GRAPE\n" "CAPRI SUN ROARIN WATER STRAWBE\n" "CAPRI SUN ROARIN WATER TROPICA\n" "CAPRI SUN ROARIN WATER WILD CH\n" "CAPRI SUN ROARING WATERS FRT P\n" "CAPRI SUN SPLASH COOLER\n" "CAPRI SUN STRAWBERRY\n" "CAPRI SUN STRAWBERRY KIWI\n" "CAPRI SUN STRW KIWI 30CT\n" "CAPRI SUN SURF COOLER\n" "CAPRI SUN TROPICAL PUNCH\n" "CAPRI SUN WILD CHERRY\n" "CAPRI SUN WLD CHRRY 30CT\n" "CAPRISUN 100% JC\n" "CAPRISUN ROARING WATERS TROPICAL FRUIT\n" "CAPSUN COASTAL COOLER 10 pk \n" "CAPSUN FRUIT PUNCH DRINK 10PK 10 ct \n" "CAPSUN PACIFIC COOLER 10PK 10 ct \n" "CS FRUIT PUNCH\n" "JUICE FRT VEG BERRY/CARRT BLST\n" "JUICES APPLE FRUIT REFRESHER\n" "JUICES BERRY FRUIT REFRESHER\n" "STRAWBERRY LEMONADE ORGANIC\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