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 single character of: a, b, c or d
    [[ab][cd]]
  • 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]
  • Character class intersection
    [\w&&[^\d]]
  • 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"(?<filename>[a-zA-Z0-9\\-\\.\\/_]+.d)(?<line>\(\d+),(?<column>\d+)\): (?<level>.+(?=:))(?<message>.*)") test_str = ("source/parsers/x509.d(149,21): Error: function `std.typecons.Nullable!(Address[]).Nullable.length() const` is not callable using argument types `(ulong)`\n" "source/parsers/x509.d(149,21): expected 0 argument(s), not 1\n" "source/parsers/x509.d(151,60): Error: cannot implicitly convert expression `parseAddress(cast(const(char)[])split(cur_line[17], header.set_seperator)[i], null)` of type `std.socket.Address` to `Address[]`\n" "source/parser.d(83,30): Error: template instance `parser.Parser.summarize!(X509)` error instantiating\n" "Error /home/steveno/dlang/dmd-2.101.0/linux/bin64/dmd failed with exit code 1.\n\n\n" "../lib/Miller.vala:32.3-32.12: error: The name `legth' does not exist in the context of `LibBalistica.Miller'\n" " 32 | this.legth = 1.0;\n" " | ^~~~~~~~~~") match = regex.search(test_str) if match: print(f"Match 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