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Swift

Functions

Declare a function with func name(parameter: Type) -> ReturnType { ... }.

Example: a function call that reads naturally

func greet(name: String) -> String {
    return "Hello, \(name)!"
}

print(greet(name: "Chidi"))
Hello, Chidi!

Notice the call site: greet(name: "Chidi"), not just greet("Chidi"). Swift's function calls typically include argument labels, which makes call sites read almost like a sentence — genuinely useful once a function takes several parameters and a bare list of values would otherwise be ambiguous about which value means what.

Example
func greet(name: String) -> String {
    return "Hello, \(name)!"
}

print(greet(name: "Chidi"))
Output
Hello, Chidi!