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

/
/
gm

Test String

Code Generator

Language

Generated Code

import Foundation let pattern = #"[\s\S]{25}(?<log_level>\w+ \d).---.\[Thread-(?<thread_id>\d+)][\s\S]{42}(?(?=: debug1): (?<internal_log_level>\w+)): (?(?=(?:.*?): )(?<module>.*?): )(?<message>.*)"# let regex = try! NSRegularExpression(pattern: pattern, options: .anchorsMatchLines) let testString = #""" 2020-03-24 07:23:26.506 INFO 6 --- [Thread-3853] S.s.ssh-output : Allocated port 40239 for remote forward to localhost:8192 2020-03-24 07:23:26.458 INFO 6 --- [Thread-3853] S.s.ssh-output : Authenticated to tunnel.alero.io ([3.225.55.134]:443). 2020-03-24 07:23:25.972 INFO 6 --- [Thread-3853] S.s.ssh-output : OpenSSH_7.6p1 Ubuntu-4ubuntu0.3, OpenSSL 1.0.2n 7 Dec 2017 2020-03-24 07:22:55.949 INFO 6 --- [Thread-3851] S.s.ssh-output : ssh_exchange_identification: Connection closed by remote host 2020-03-26 14:50:11.591 INFO 6 --- [Thread-3853] S.s.ssh-output : debug1: channel 1: connected to localhost port 8192 2020-03-26 14:50:11.591 INFO 6 --- [Thread-3853] S.s.ssh-output : debug1: confirm forwarded-tcpip 2020-03-26 14:50:11.591 INFO 6 --- [Thread-3853] S.s.ssh-output : debug1: channel 1: new [192.168.33.160] 2020-03-26 14:50:11.591 INFO 6 --- [Thread-3853] S.s.ssh-output : debug1: connect_next: host localhost ([127.0.0.1]:8192) in progress, fd=5 2020-03-26 14:50:11.589 INFO 6 --- [Thread-3853] S.s.ssh-output : debug1: client_request_forwarded_tcpip: listen 0.0.0.0 port 40239, originator 192.168.33.160 port 37440 2020-03-26 14:50:11.589 INFO 6 --- [Thread-3853] S.s.ssh-output : debug1: client_input_channel_open: ctype forwarded-tcpip rchan 2 win 2097152 max 32768 2020-03-26 14:50:11.372 INFO 6 --- [Thread-3853] S.s.ssh-output : debug1: channel 0: connected to localhost port 8192 2020-03-26 14:50:11.372 INFO 6 --- [Thread-3853] S.s.ssh-output : debug1: confirm forwarded-tcpip 2020-03-26 14:50:11.372 INFO 6 --- [Thread-3853] S.s.ssh-output : debug1: channel 0: new [192.168.62.96] 2020-03-26 14:50:11.372 INFO 6 --- [Thread-3853] S.s.ssh-output : debug1: connect_next: host localhost ([127.0.0.1]:8192) in progress, fd=4 2020-03-26 14:50:11.372 INFO 6 --- [Thread-3853] S.s.ssh-output : debug1: client_request_forwarded_tcpip: listen 0.0.0.0 port 40239, originator 192.168.62.96 port 59736 2020-03-26 14:50:11.372 INFO 6 --- [Thread-3853] S.s.ssh-output : debug1: client_input_channel_open: ctype forwarded-tcpip rchan 1 win 2097152 max 32768 2020-03-26 14:50:10.872 INFO 6 --- [Thread-3853] S.s.ssh-output : debug1: channel 0: free: 192.168.62.96, nchannels 2 2020-03-26 14:49:11.329 INFO 6 --- [Thread-3853] S.s.ssh-output : debug1: channel 0: connected to localhost port 8192 2020-03-26 14:49:11.329 INFO 6 --- [Thread-3853] S.s.ssh-output : debug1: confirm forwarded-tcpip 2020-03-26 14:49:11.329 INFO 6 --- [Thread-3853] S.s.ssh-output : debug1: channel 0: new [192.168.62.96] 2020-03-26 14:49:11.329 INFO 6 --- [Thread-3853] S.s.ssh-output : debug1: connect_next: host localhost ([127.0.0.1]:8192) in progress, fd=4 2020-03-26 14:49:11.328 INFO 6 --- [Thread-3853] S.s.ssh-output : debug1: client_request_forwarded_tcpip: listen 0.0.0.0 port 40239, originator 192.168.62.96 port 58296 2020-03-26 14:49:11.328 INFO 6 --- [Thread-3853] S.s.ssh-output : debug1: client_input_channel_open: ctype forwarded-tcpip rchan 1 win 2097152 max 32768 2020-03-26 14:49:10.875 INFO 6 --- [Thread-3853] S.s.ssh-output : debug1: channel 0: free: 192.168.33.160, nchannels 2 2020-03-26 14:49:03.819 INFO 6 --- [Thread-3853] S.s.ssh-output : debug1: channel 1: free: 192.168.33.160, nchannels 3 2020-03-26 14:48:49.820 INFO 6 --- [Thread-3853] S.s.ssh-output : debug1: channel 8: free: 192.168.62.96, nchannels 4 2020-03-26 14:48:49.820 INFO 6 --- [Thread-3853] S.s.ssh-output : debug1: channel 7: free: 192.168.62.96, nchannels 5 2020-03-26 14:48:49.820 INFO 6 --- [Thread-3853] S.s.ssh-output : debug1: channel 5: free: 192.168.33.160, nchannels 6 2020-03-26 14:48:49.819 INFO 6 --- [Thread-3853] S.s.ssh-output : debug1: channel 3: free: 192.168.33.160, nchannels 7 2020-03-26 14:48:49.819 INFO 6 --- [Thread-3853] S.s.ssh-output : debug1: channel 2: free: 192.168.33.160, nchannels 8 """# let stringRange = NSRange(location: 0, length: testString.utf16.count) let matches = regex.matches(in: testString, range: stringRange) var result: [[String]] = [] for match in matches { var groups: [String] = [] for rangeIndex in 1 ..< match.numberOfRanges { let nsRange = match.range(at: rangeIndex) guard !NSEqualRanges(nsRange, NSMakeRange(NSNotFound, 0)) else { continue } let string = (testString as NSString).substring(with: nsRange) groups.append(string) } if !groups.isEmpty { result.append(groups) } } print(result)

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 Swift 5.2, please visit: https://developer.apple.com/documentation/foundation/nsregularexpression