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"([A-Z ]+)\n--(.*?)--\n(.*?)\n\n", flags=re.MULTILINE | re.DOTALL) test_str = ("Washington, DC November 27, 2019\n" "USDA Truck Rate Report\n\n" "WA_FV190\n\n" "FIRST PRICE RANGE FOR WEEK OF NOVEMBER 20-26 2019\n" "SECOND PRICE MOSTLY FOR TUESDAY NOVEMBER 26 2019\n\n" "PERCENTAGE OF CHANGE FROM TUESDAY NOVEMBER 19 2019 SHOWN IN ().\n\n" "In areas where rates are based on package rates, per-load rates were\n" "derived by multiplying the package rate by the number of packages in\n" "the most usual load in a 48-53 foot trailer.\n\n" "CENTRAL AND WESTERN ARIZONA\n" "-- LETTUCE, BROCCOLI, CAULIFLOWER, ROMAINE AND LEAF LETTUCE SLIGHT SHORTAGE\n" "--\n\n" "ATLANTA 5100 5500\n" "BALTIMORE 6300 6600\n" "BOSTON 7000 7300\n" "CHICAGO 4500 4900\n" "DALLAS 3400 3800\n" "MIAMI 6400 6700\n" "NEW YORK 6600 6900\n" "PHILADELPHIA 6400 6700\n\n" " 2019 2018\n\n" " NOV 17-23 NOV 18-24\n\n" "U.S. 25,701 22,956\n" "IMPORTS 13,653 15,699\n" " ------------ --------------\n" "sum 39,354 38,655") 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