Swift online compiler

Write, Run & Share Swift code online using OneCompiler’s Swift online compiler for free. It’s a fast and user-friendly platform to explore Swift programming right from your browser. Ideal for students, beginners, and professionals looking to prototype or test Swift code.

About Swift

Swift is a powerful and intuitive programming language developed by Apple for iOS, macOS, watchOS, and tvOS app development. It's designed to be safe, fast, and expressive, with modern features like optionals, closures, and type inference.

Sample Code

The following is a simple Swift program that prints a greeting:

import Foundation

print("Hello, OneCompiler!")

Taking inputs (stdin)

OneCompiler’s Swift editor supports standard input via the I/O tab. Here’s a sample Swift program that takes a user’s name and prints a greeting:

import Foundation

if let name = readLine() {
    print("Hello, \(name)!")
}

Syntax Basics

Variables

var age = 25          // Mutable variable
let name = "Swift"     // Constant

Data Types

Type	Description
Int	Whole numbers
Double	Decimal numbers
String	Sequence of characters
Bool	true or false
Array	Ordered collection
Dictionary	Key-value pairs

Conditionals

let score = 75
if score >= 50 {
    print("Pass")
} else {
    print("Fail")
}

Loops

For-in loop

for i in 1...5 {
    print(i)
}

While loop

var i = 1
while i <= 5 {
    print(i)
    i += 1
}

Repeat-While loop

var j = 1
repeat {
    print(j)
    j += 1
} while j <= 5

Functions

func greet(name: String) {
    print("Hello, \(name)!")
}

greet(name: "OneCompiler")

func add(a: Int, b: Int) -> Int {
    return a + b
}

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This guide provides a quick reference to Swift programming syntax and features. Start writing Swift code using OneCompiler’s Swift online compiler today!