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"([A-Z0-9-_]+).txt:\s?\s?([A-Z0-9-_:]+)\s+(\d+:\d+)|([A-Z0-9-_]+).txt:\s+(\w{6})\s+(\d+:\d+)" test_str = ("RTARSPO0302.txt:MVNO_AMERICANET 26615:20891087 \n" "RTARSPO0302.txt: import 26615:30150 IPV4 Unicast \n" "RTARSPO0302.txt: import 26615:30200 IPV4 Unicast \n" "RTARSPO0302.txt:RAN_SHARING_OI 26615:20302087 \n" "RTARSPO0302.txt: import 26615:30200 IPV4 Unicast \n" "RTARSPO0302.txt: import 26615:30206 IPV4 Unicast \n" "RTARSPO0302.txt: import 26615:30301 IPV4 Unicast \n" "RTARSPO0302.txt: import 26615:30320 IPV4 Unicast \n" "RTARSPO0302.txt: export 26615:30301 IPV4 Unicast \n" "RTARSPO0302.txt: export 26615:303027 IPV4 Unicast \n" "RTARSPO0302.txt:TIMGPRS 26615:20203087 \n" "RTARSPO0302.txt: import 26615:30200 IPV4 Unicast \n" "RTARSPO0302.txt: import 26615:30301 IPV4 Unicast \n" "RTARSPO0302.txt: export 26615:30200 IPV4 Unicast \n" "RTARTSA0101.txt:DCN 26615:20705093 \n" "RTARTSA0101.txt: import 26615:30700 IPV4 Unicast \n" "RTARTSA0101.txt: export 26615:30700 IPV4 Unicast \n" "RTARTSA0101.txt:RAN_SHARING_OI 26615:20301093 \n" "RTARTSA0101.txt: import 26615:30301 IPV4 Unicast \n" "RTARTSA0101.txt: export 26615:30301 IPV4 Unicast \n" "R") 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