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"^\[[a-z-]*\]\s[\w\d\s\-\=\"\.\:\@]+") test_str = ("[access-control]\n" "realm-id = \"name2\"\n" "description = \"Register_to_Bryansk_RTU\"\n" "source-address = \"0.0.0.0\"\n" "destination-address = \"0.0.0.0:5060\"\n" "application-protocol = \"SIP\"\n" "transport-protocol = \"ALL\"\n" "[access-control]\n" "access = \"permit\"\n" "average-rate-limit = \"0\"\n" "trust-level = \"high\"\n" "minimum-reserved-bandwidth = \"0\"\n" "invalid-signal-threshold = \"0\"\n" "maximum-signal-threshold = \"0\"\n" "[access-control]\n" "untrusted-signal-threshold = \"0\"\n" "nat-trust-threshold = \"0\"\n" "max-endpoints-per-nat = \"0\"\n" "nat-invalid-message-threshold = \"0\"\n" "deny-period = \"30\"\n" "cac-failure-threshold = \"0\"\n" "untrust-cac-failure-threshold = \"0\"\n" "[access-control]\n" "last-modified-by = \"admin@0.0.0.0\"\n" "last-modified-date = \"2015-01-22 09:01:19\"\n" "[access-control]\n" "realm-id = \"name\"\n" "description = \"\"\n" "source-address = \"0.0.0.0\"\n" "destination-address = \"0.0.0.0:5060\"\n" "application-protocol = \"SIP\"\n" "transport-protocol = \"ALL\"\n" "access = \"permit\"\n" "average-rate-limit = \"0\"\n" "trust-level = \"high\"\n" "minimum-reserved-bandwidth = \"0\"\n" "invalid-signal-threshold = \"0\"\n" "maximum-signal-threshold = \"0\"\n" "untrusted-signal-threshold = \"0\"\n" "nat-trust-threshold = \"0\"\n" "max-endpoints-per-nat = \"0\"\n" "nat-invalid-message-threshold = \"0\"\n" "deny-period = \"30\"\n" "cac-failure-threshold = \"0\"\n" "untrust-cac-failure-threshold = \"0\"\n" "last-modified-by = \"admin@0.0.0.0\"\n" "last-modified-date = \"2014-10-23 11:26:39\"") 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