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

Substitution

Processing...

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 = ("03/01/2022,7−ELEVEN − TTSH LEV SINGAPORE SG,,SGD 1.10\n" "03/01/2022,7−ELEVEN − TTSH LEV SINGAPORE SG,,SGD 2.00\n" "03/01/2022,HEAVENLYWANG@HWMW SINGAPORE SG,,SGD 10.60\n" "03/01/2022,DON DON DONKI SINGAPORE SG,,SGD 11.60\n" "03/01/2022,LIFELINE CORPORATIO SINGAPORE SG,,SGD 106.00\n" "04/01/2022,ESSO−CHEERS BY FP SINGAPORE SG,,SGD 2.50\n" "04/01/2022,MCDONALD'S (QSC) SINGAPORE SG,,SGD 7.10\n" "04/01/2022,SHELL PAYA LEBAR MA SINGAPORE SG,,SGD 17.35\n" "03/01/2022,PAYMENT − THANK YOU 8,978.47CR\n" "04/01/2022,SINGPOST − SAM KIOS SINGAPORE SG,,SGD 2.40\n" "04/01/2022,Artisan Boulangerie Singapore SG,,SGD 9.94\n" "05/01/2022,W S GO & ASSOCIATES SINGAPORE SG,,SGD 374.50\n" "06/01/2022,ECCELLENTE MARINA SINGAPORE SG,,SGD 1.90\n" "06/01/2022,COLD STORAGE−GREAT SINGAPORE SG,,SGD 16.10\n" "06/01/2022,STARBUCKS@GREAT WLD SINGAPORE SG,,SGD 18.00\n" "06/01/2022,STARBUCKS@GREAT WLD SINGAPORE SG,,SGD 18.00\n" "06/01/2022,HIRAKI SINGAPORE SG,,SGD 30.48\n" "06/01/2022,SINGAPORE NATIONAL SINGAPORE SG,,SGD 154.08\n" "07/01/2022,KRAFTWICH @ PLSQ SINGAPORE SG,,SGD 20.30\n" "07/01/2022,KIM CHOO HOLDINGS P SINGAPORE SG,,SGD 33.00\n" "08/01/2022,STARBUCKS@WIKIE EDG SINGAPORE SG,,SGD 18.00\n" "10/01/2022,ECCELLENTE MARINA SINGAPORE SG,,SGD 1.90\n" "10/01/2022,MCDONALD'S (PSA) SINGAPORE SG,,SGD 17.80\n" "11/01/2022,BRAWN AND BRAINS SINGAPORE SG,,SGD 31.90\n" "11/01/2022,12 Jan A POKE THEORY−TRIPL SINGAPORE SG,,SGD 16.50") subst = "$1 DR" # You can manually specify the number of replacements by changing the 4th argument result = re.sub(regex, subst, test_str, 0, re.MULTILINE) if result: print (result) # 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