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

/
/
g

Test String

Code Generator

Language

Generated Code

import Foundation let pattern = #"workspaces\/(?<workspace_name>[^\/]+)\/runs\/run-(?<workspace_id>[^\"\\]+)"# let regex = try! NSRegularExpression(pattern: pattern) let testString = #""" 10.218.136.20 - - [30/Jun/2023:02:36:37 +0000] "GET /api/v2/workspaces/ws-ukz9TnHNE9kN4eCa?include=agent_pool%2Ccurrent_configuration_version%2Ccurrent_run%2Ccurrent_state_version%2Clocked_by%2Creadme%2Coutputs HTTP/1.1" 304 0 "https://terraform.srv.companyname.com.au/app/customer/workspaces/a00ccc-tfe-dev02-customer_infra/runs/run-ACevPzmMTYE6UP5e" "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/114.0.0.0 Safari/537.36" 10.218.136.20 - - [30/Jun/2023:02:36:40 +0000] "GET /api/v2/runs/run-Y63d5qeBk3pDHpJZ/run-events?include=comment%2Cactor HTTP/1.1" 304 0 "https://terraform.srv.companyname.com.au/app/customer/workspaces/a00964-tfe-test-customer_infra_main/runs/run-Y63d5qeBk3pDHpJZ" "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/114.0.0.0 Safari/537.36" """# 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