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"(?m)^([^\r\n]+)\s*\n([^\r\n]+)\s*\n([^\r\n]+):\s*([^\r\n]+)\s*\n([^\r\n]+):\s*([^\r\n]+)(?:\s*\n([^\r\n]+):\s*([^\r\n]+))?\s*\nDirections:\s*\n((?:.+\s*\n?)+?)(?=^[^\r\n]+\s*\n[^\r\n]+\s*\n[^\r\n]+:|\z)" test_str = ("Bob's Diner\n" "Reefer\n" "Location: Mike's Beef Barn\n" "Time: 1,584\n" "Stop: Highway Hotel.\n" "Directions:\n" "Go south on Broadway.\n" "Get on freeway 30 South. Exit Main St.\n" "Go south on Main to Highway Hotel.\n" "Go north on Main. Go east on Highway 15. Exit Market St.\n" "1522 Market St.\n" "Comfy Pillows and Mattresses\n" "Dry Van\n" "Location: Innovative Furniture\n" "Time: 223\n" "Directions:\n" "Turn right and go to Seville Ave.\n" "Turn left on St. Michael St.\n" "Go to end at the Comfy Sign.\n" "Washington County Construction\n" "Low Boy\n" "Location: Marble Quarry in Gainesville.\n" "Time: 1,135\n" "Stop: Mountainside Motel.\n" "Directions:\n" "Make a U-turn on Alameda Ave. and a right on Chantilly Lane.\n" "Get on freeway 67 East.\n" "Pass the Hospital and Exit Seward St.\n" "Turn left on Coral St. to Mountainside Motel on right.\n" "Exit motel and go east on Jefferson and then right on Belhaven.\n" "Follow Joelle Ln. to Hwy 49.\n" "Turn right at the Red Hill Junction. Go east on Harewood Rd.\n" "Turn left on Blue Heron St.\n" "8964 Red Rooster St.\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