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
  • Match everything enclosed
    (?:...)
  • Capture everything enclosed
    (...)
  • 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

r"
"
mg

Test String

Code Generator

Language

Generated Code

import Foundation let pattern = #"(PostgreSQL (?P<psql_major>\d{1,2})\.(?P<psql_minor>\d{1,2})(?P<psql_opt_patch>\.\d{1,2})?, )?Aurora PostgreSQL release (?P<aurora_psql_major>\d{1,2})\.(?P<aurora_psql_minor>\d{1,2})(?P<aurora_psql_opt_patch>\.\d{1,2})?(?P<release_or_deprecation>\,\s(?P<release_data>.*)|\s\(Deprecated on (?P<deprecation_date>.*)\))?"# let regex = try! NSRegularExpression(pattern: pattern, options: .anchorsMatchLines) let testString = #""" PostgreSQL 12.6, Aurora PostgreSQL release 4.1 (Deprecated on July 15, 2022) PostgreSQL 12.4, Aurora PostgreSQL release 4.0 (Deprecated on July 15, 2022) Aurora PostgreSQL release 14.3.1, July 6, 2022 PostgreSQL 9.6.8, Aurora PostgreSQL release 1.2 (Deprecated on October 28, 2021) PostgreSQL 9.6.8, Aurora PostgreSQL release 1.2.4 PostgreSQL 14.5, Aurora PostgreSQL release 1.2 Aurora PostgreSQL release 14.3.1, Deprecated on October 28, 2021) """# 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