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*((https?:\/\/)((\S+\.+\S+)|(\[?(\S+:)+\S+\]?)|({.*}.*))?(?::\d+)?({.*}.*)?|({.*}.*))\s*$ """# let regex = try! NSRegularExpression(pattern: pattern, options: .anchorsMatchLines) let testString = ##""" http://foo.bar https://foo.bar https://foo.bar/{foo} {foo} IPv4 http://foo123.bar/{Fave Country (South Africa):3.1} https://foo123.bar/{field :1} https://{field:1} https://foo.bar/{field:1}/ https://foo.bar/{field:1}:8080?name=value#fragment http://foo.bar https://foo.bar/path/to/resource http://192.168.0.1:8080/path/to/file/?name=value https://[2001:db8::1]:443/resource Starting with merge tag {field:1} {field:1}/path/to?name=value#fragment IPv6 https://2001:0db8:85a3:0000:0000:8a2e:0370:7334 https://001:db8:85a3::8a2e:370:7334 https://::1 https://::ffff:192.0.2.128 https://[fe80::1%25eth0]/{field :1} https://fe80::1%eth0 https://ff02::1 https://2001:4860:4860::8888 https://2001:db8::2:1 https://fd12:3456:789a:1::1 https://1234:5678:90ab:cdef::1 NON VALID: htp://foo.bar //foo.bar dfdf{field:1} http://foo foo https//foo https://foodfdf htp://foo.bar foo.bar http://foo foo.bar/{field:1} """## 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