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 = ##"^\(\s*[0-9]+\)\[[a-zA-Z0-9\s:]*\|\s*[0-9]{1,5}\:[0-9]{3}\s*(?:\[[0-9]{1,3}\:[0-9]{1,3}\])?\]\{[0-9]{1,4}\}[a-zA-Z0-9\s:@\/~]+\(?:.+\)[\$|#]\s{1}(?<!\n)(.+)$"## let regex = try! NSRegularExpression(pattern: pattern, options: .anchorsMatchLines) let testString = ##""" ( 8)[Thu Sep 01 09:44:38| 0:000]{157}jhyland@jhmac:~(✓)$ whoami ( 8)[Thu Sep 01 09:44:42| 0:000]{158}jhyland@jhmac:~(✓)$ uptime ( 8)[Thu Sep 01 09:44:45| 1:000]{159}jhyland@jhmac:~(✓)$ pwd Documents/scripts/ ( 8)[Thu Sep 01 09:44:51| 1:000]{160}jhyland@jhmac:~(✓)$ false ( 8)[Thu Sep 01 09:44:54| 0:000]{161}jhyland@jhmac:~(123)$ d ( 8)[Thu Sep 01 09:44:38| 0:000]{157}jhyland@jhmac:~(✓)$ whoami ( 8)[Thu Sep 01 09:44:42| 0:000]{158}jhyland@jhmac:~(✓)$ uptime ( 8)[Thu Sep 01 09:44:45| 1:000]{159}jhyland@jhmac:~(✓)$ pwd Documents/scripts/ ( 8)[Thu Sep 01 09:44:51| 1:000]{160}jhyland@jhmac:~(✓)$ false ( 8)[Thu Sep 01 09:44:54| 0:000]{161}jhyland@jhmac:~(0)$ ( 7)[Thu Sep 01 09:17:30| 1:000]{1}jhyland@jhmac:~(✓)$ man idk ( 7)[Thu Sep 01 09:17:32| 2:000]{2}jhyland@jhmac:~(0)$ man file ( 7)[Thu Sep 01 09:50:51| 1998:000 [00:33]]{3}jhyland@jhmac:~(✓)$ ( 7)[Thu Sep 01 09:54:08| 0:000]{1}jhyland@jhmac:~(✓)$ . ~/.bash_profile ( 7)[Thu Sep 01 09:54:14| 0:000]{2}jhyland@jhmac:~(✓)$ return_code ( 7)[Thu Sep 01 09:54:17| 0:000]{3}jhyland@jhmac:~(0)$ sudo su - ( 7)[Thu Sep 01 10:05:49| 0:000]{1}root@jhmac:~(✓)# whoami ( 7)[Thu Sep 01 10:06:24| 0:000]{2}root@jhmac:~(✓)# cd ~ ( 7)[Thu Sep 01 10:06:29| 0:000]{3}root@jhmac:~(✓)# cd /tmp ( 7)[Thu Sep 01 09:54:08| 0:000]{1}jhyland@jhmac:~(✓)$ . ~/.bash_profile ( 7)[Thu Sep 01 09:54:14| 0:000]{2}jhyland@jhmac:~(✓)$ return_code ( 7)[Thu Sep 01 09:54:17| 0:000]{3}jhyland@jhmac:~(0)$ sudo su - ( 7)[Thu Sep 01 10:05:49| 0:000]{1}root@jhmac:~(✓)# whoami ( 7)[Thu Sep 01 10:06:24| 0:000]{2}root@jhmac:~(✓)# cd ~ ( 7)[Thu Sep 01 10:06:29| 0:000]{3}root@jhmac:~(✓)# cd /tmp ( 7)[Thu Sep 01 10:06:33| 0:000]{4}root@jhmac:/tmp(✓)# cd ~/.ssh/ ( 7)[Thu Sep 01 10:15:35| 0:000]{5}root@jhmac:~/.ssh(✓)# exit ( 7)[Thu Sep 01 10:15:39| 591:000 [00:09]]{4}jhyland@jhmac:~(✓)$ cd Documents/scripts/javascript/ ( 7)[Thu Sep 01 10:15:44| 0:000]{5}jhyland@jhmac:~/Documents/scripts/javascript(✓)$ ls """## 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