About Swift

Swift is a high-performance system programming language. It has a clean and modern syntax, offers seamless access to existing C and Objective-C code and frameworks, and is memory safe by default.

Although inspired by Objective-C and many other languages, Swift is not itself a C-derived language. As a complete and independent language, Swift packages core features like flow control, data structures, and functions, with high-level constructs like objects, protocols, closures, and generics. Swift embraces modules, eliminating the need for headers and the code duplication they entail.

Installing Swift

To install Swift on Fedora, simply type:

$ sudo dnf install swiftlang

You can now start Swift’s REPL (read-eval-print loop), which is an interactive session by invoking the swift command in the terminal. The Swift REPL will start like this:

$ swift
Swift version 5.6.1 (swift-5.6.1-RELEASE)
Target: aarch64-unknown-linux-gnu

Welcome to Swift!

Subcommands:

  swift build      Build Swift packages
  swift package    Create and work on packages
  swift run        Run a program from a package
  swift test       Run package tests
  swift repl       Experiment with Swift code interactively (default)

  Use `swift --help` for descriptions of available options and flags.

  Use `swift help <subcommand>` for more information about a subcommand.

Welcome to Swift version 5.6.1 (swift-5.6.1-RELEASE).
Type :help for assistance.
  1>

Now, you can run Swift commands inside the REPL.

  1> let x = 6
x: Int = 6
  2> let y = 7
y: Int = 7
  3> print("The answer is \(x * y)")
The answer is 42
  4>

To exit the REPL, press Ctrl + D.

Swift source files have the file extension .swift. Create a Swift program your_source.swift. You can compile the file using the command below:

$ swiftc your_source.swift

This will compile the file and create an executable file your_source in the current directory. You can run the file like so:

$ ./your_source

To see the manual page of swift, simply type:

$ man swift

References

• Swift Documentation

Authors: Ron Olson