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
  • Match everything enclosed
    (?:...)
  • Capture everything enclosed
    (...)
  • 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

r"
"
g

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"(\d+)\s((\d+)\s(.*)\s?(St|Rd|Ave|Dr|Pl|Sq|Ln))\s?(W|E|N|S)?,\s(.*),\s((\w+)\s(.*))\n" test_str = ("1 1067 Niagara Stone Rd, Niagara-On-The-Lake, ON L0S 1J0\n" "2 4260 Mountainview Rd, Lincoln, ON L0R 1B2\n" "4 1091 Hutchinson Rd, Haldimand, ON N0A 1K0\n" "16 3753 Quarry Rd, Lincoln, ON L0R 1B2\n" "19 131 River Rd, Haldimand, ON N1A 2W3\n" "20 111 Garrison Village Dr, Niagara-On-The-Lake, ON L0S 1J0\n" "21 3678 Victoria Ave, Lincoln, ON L0R 2C0\n" "24 3751 King St, Lincoln, ON L0R 2C0\n" "34 2878 Holland Rd, Thorold, ON L0S 1E6\n" "35 103 Overholt Rd, Pelham, ON L0S 1M0\n" "47 3930 Cherry Ave, Lincoln, ON L0R 1B1\n" "48 4016 Mountain St, Lincoln, ON L0R 1B7\n" "49 135 Taylor Rd, Niagara-On-The-Lake, ON L0S 1J0\n" "50 5943 Sylvia Pl, Niagara Falls, ON L2G 1S9\n" "51 6863 Lundys Ln, Niagara Falls, ON L2G 1V7\n" "55 290 John St E, Niagara-On-The-Lake, ON L0S 1J0\n" "56 5600 King St W, Lincoln, ON L0R 1B3\n" "63 3900 Cherry Ave, Lincoln, ON L0R 2C0\n" "64 282 Ridge Rd N, Fort Erie, ON L0S 1N0\n" "65 4352 Mountainview Rd, Lincoln, ON L0R 1B2\n" "74 1339 Lakeshore Rd, Niagara-On-The-Lake, ON L0S 1J0\n" "75 1425 Lakeshore Rd, Niagara-On-The-Lake, ON L0S 1J0\n" "82 400 Main St W, Grimsby, ON L3M 1T2\n" "83 3620 Moyer Rd, Lincoln, ON L0R 2C0\n" "87 1625 Haist St, Pelham, ON L0S 1E0\n" "91 905 Canborough Rd, Pelham, ON L0S 1C0") matches = re.finditer(regex, test_str) 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