Playground

A real Swift interpreter running in this tab. Write a program and print to the console, or define a View and see it render. Nothing leaves your device.

struct Task {
    let title: String
    var isDone: Bool
}

var tasks = [
    Task(title: "Write the parser", isDone: true),
    Task(title: "Render the preview", isDone: true),
    Task(title: "Ship it", isDone: false),
]

let remaining = tasks.filter { !$0.isDone }
print("\(remaining.count) of \(tasks.count) left")

for task in tasks {
    let mark = task.isDone ? "x" : " "
    print("[\(mark)] \(task.title)")
}

The runtime covers the language the curriculum teaches — types, protocols, generics, error handling, and structured concurrency — but it is an interpreter, not a compiler. Type errors surface when the line runs rather than before. See what it can and cannot do.