Users' questions

Does Swift have regex?

Does Swift have regex?

Apple provides support for regular expressions on all of its platforms – iOS, macOS, tvOS, and even watchOS – all using the same class, NSRegularExpression . It’s an extremely fast and efficient way to search and replace complex text tens of thousands of times, and it’s all available for Swift developers to use.

What are regular expressions in Swift?

A regular expression can match its pattern one or more times on a string. Within each match, there may be one or more capture groups , which are designated by enclosing by parentheses in the regex pattern.

What are regex capture groups?

Capturing groups are a way to treat multiple characters as a single unit. They are created by placing the characters to be grouped inside a set of parentheses. For example, the regular expression (dog) creates a single group containing the letters “d” “o” and “g” .

How do you match a string in Swift?

Compare two strings ignoring case in Swift

  1. let a = “a” let capitalA = “A” a. compare(capitalA, options: .
  2. let a = “a” let capitalA = “A” a. lowercased() == capitalA.
  3. let street = “Straße” let alsoStreet = “STRASSE” print(street. lowercased())
  4. let e = “e” let eWithAcuteAccent = “é” e. compare(eWithAcuteAccent, options: .

How do you add or condition in regex?

This pattern will match:

  1. \d+ : One or more numbers.
  2. \s+ : One or more whitespaces.
  3. [A-Z\s]+ : One or more uppercase characters or space characters.
  4. \s+ : One or more whitespaces.
  5. [A-Z][A-Za-z\s]+ : An uppercase character followed by at least one more character (uppercase or lowercase) or whitespaces.

What is $1 regex?

For example, the replacement pattern $1 indicates that the matched substring is to be replaced by the first captured group.

What is comparable in Swift?

The Comparable protocol allows use to use the < , > , <= , and >= operators with conforming data types, which in turn means that Swift knows how to sort arrays of those types.

Is it pronounced regex or regex?

Instead, I normally use “regex.” It just rolls right off the tongue (“it rhymes with “FedEx,” with a hard g sound like “regular” and not a soft one like in “Regina”) and it is amenable to a variety of uses like “when you regex …,” “budding regexers,” and even “regexification.”

Is regex a programming language?

Regular Expressions are a particular kind of formal grammar used to parse strings and other textual information that are known as “Regular Languages” in formal language theory. They are not a programming language as such.

How to use regex validation in Swift 5?

Regex Validation in Swift 5 [Email, Phone, and more!] Learn how to create and use regular expressions in Swift to validate emails, phone numbers, usernames, passwords, and dates. Validating user input is a common task in dynamic iOS and macOS apps.

Can you use regular expressions in Swift 4?

Recent additions in Swift 4 and 5 make it much, much nicer to use NSRegularExpression when you need to. Let’s interrogate each of these points, in order: You may be surprised to learn that you can, in fact, use regular expressions in a Swift one-liner — you just have to bypass NSRegularExpression entirely.

When to use nsregularexpression [ A-Z ] in Swift?

NSRegularExpression(pattern: ” [a-z]at”) [a-z] is regex’s way of specifying any letter from “a” through “z”. This is a throwing initializer because you might attempt to provide an invalid regular expression, but here we have hard-coded a correct regex so there’s no need to try to catch errors.

How to match a string to a pattern in Swift?

Matching Strings Against Patterns When you import the Foundation framework, the Swift String type automatically gets access to NSString instance methods and initializers. Among these is range (of:options:range:locale:), which finds and returns the first range of the specified string.