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
Processing...

Test String

Code Generator

Language

Generated Code

import re regex = re.compile(r"((anticorpi|ac|ciroza).*?)?(hepatita (cr(onica)? )?(.*?))?(vh|hv|virus )([bcd])(.*?(vh|hv|virus )([bcd]))?", flags=re.IGNORECASE) test_str = ("HEPATITA CRONICA CU VHC\n" "HEPATITA CRONICA - VHC\n" "HEPATITA CRONICA DE ETIOLOGIE MIXTA NUTRITIONALA SI VHC\n" "HEPATITA CRONICA CU VHC.\n" "HEPATITA CRONICA CU VHC.\n" "HEPATITA CRONICA CU VHC\n" "HEPATITA CRONICA - VHB\n" "HEPATITA CRONICA CU VIRUS C\n" "HEPATITA CRONICA\n" "HEPATITA CRONICA CU VHB\n" "HEPATITA CRONICA MEDICAMENTOASA.\n" "HEPATITA DE ETIOLOGIE POSIBIL VIRALA IN APP\n" "HEPATITA VIRUS C\n" "HEPATITA CRONICA CU VHB\n" "HEPATITA CRONICA CU VHC \n" "Hepatita cr cu virus B\n" "HEPATITA VIRUS C\n" "HEPATITA VIRALA (VHA-####) \n" "HEPATITA CRONICA VHB\n" "HEPATITA CRONICA CU VHC\n" "HEPATITA CRONICA- VHB\n" "HEPATITA CRONICA CU VHC \n" "HEPATITA CRONICA CU VHC(####)\n" "HEPATITA CRONICA DE ETIOLOGIE NEPRECIZATA \n" "HEPATITA CRONICA CU VHB\n" "HEPATITA CRONICA VHC\n" "HEPATITA CRONICA VIRALA CU VHC\n" "HEPATITA VIRALA -VHC \n" "HEPATITA CRONICA CU VHC\n" "Hepatita cronica cu virus B\n" "HEPATITA CRONICA CU VHB +VHC\n" "HEPATITA CRONICA VHB+VHC \n" "HEPATITA VIRALA C \n" "HEPATITA CRONICA CU VHC \n" "HEPATITA CRONICA CU VHB\n" "HEPATITA CRONICA VHB+VHC\n" "HEPATITA CRONICA CU VHB \n" "HEPATITA B\n" "Hepatita cronica.\n" "HEPATITA CRONICA CU VHB\n" "CIROZA HEPATICA SECUNDARA INFECTIEI CU VHB SI VHD \n" "CIROZA HEPATICA VHB +VHD\n" "CIROZA HEPATICA SECUNDARA INFECTIEI CU VHB SI VHD\n" "HVB, HVC \n" "HVB+ HVC \n" "HVC + HVB \n" "HEPATITA CU HVC \n" "HEPATITA CRONICA HVC \n" "HEPATITA CU HVC \n" "CIROZA HEPATICA -HVC CHILD A\n" "Ac AntiHVC +, HEPATOSPLENOMEGALIE\n" "HEPATITA CU HVC \n" "HEPATITA CRONICA HVC\n" "ANTICORPI ANTI-HVC+\n") matches = regex.finditer(test_str) for match_num, match in enumerate(matches, start=1): print(f"Match {match_num} was found at {match.start()}-{match.end()}: {match.group()}") for group_num, group in enumerate(match.groups(), start=1): print(f"Group {group_num} found at {match.start(group_num)}-{match.end(group_num)}: {group}")

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