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

/
/

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"TR\$.+?(?=\n)" test_str = ("TR$1b3abc T0b0 4 0 20151117 062231 7 14 15 c0a81e03 0 0 1 00A 3 481915101 3 481915101 0 1 3 90047975097350 001 0 3 975097350 1 9 F10 XT 131550-251897 FT110393_RT43 loop[gw_sip,PR970149981] 0 D00c 3108 222e42 E007 020103 H018 3 481915101 10 TRAFTERM G033 20151117 06223185 0000000050 0000000772 0000001484 V013 0 20 0 0 0 SIP_OUT O038 7109 58056 56252 354 343 0 4 0 IP2TDM 192.168.31.6:6372 Z02c 20925-DY-0001b6a8-523106f36@sip.mystream.fr\n" "GO$18c T0a3 185 0 20151117 063030 6 17 18 c0a81e03 1 0 1 00A 3 139947700 3 139947752 0 1 3 629452310 001 0 3 629452310 1 24 B10 XT 265720-251900 SIP loop[gw_sip,PEER_SFR_2] 0 D00c 3108 222e48 G033 20151117 06303070 0000000071 0000001140 0000001731 L008 1 1 3 1 E007 020103 Y005 3 15 V012 8 20 0 0 0 SIP_IN V013 8 20 0 0 0 SIP_OUT Z02c 21325-EZ-0001b7ed-3b997c5d2@sip.mystream.fr Z00d 70b7375a@pbx") matches = re.search(regex, test_str) if matches: print ("Match was found at {start}-{end}: {match}".format(start = matches.start(), end = matches.end(), match = matches.group())) for groupNum in range(0, len(matches.groups())): groupNum = groupNum + 1 print ("Group {groupNum} found at {start}-{end}: {group}".format(groupNum = groupNum, start = matches.start(groupNum), end = matches.end(groupNum), group = matches.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