value-initializers.md

Value Initializers

Values have initializers similar to classes, however there is no base initializer to call. The initializer still has two phases and enforces definite assignment of fields before the self value can be used.

Like with class initializers, they have a self parameter. However, this parameter is passed by value and then the self value is returned by value.

public const value example
{
    public init(self)
    {
    }

    public init named(self)
    {
    }
}

let x = example();
let y = example.named();

Default Initializers

A value without any initializers will have a default initializer generated for it.

Field Initialization Shorthand

Just like class initializers, there is a shorthand for initializing fields.

public init(self, .field)
{
}

Definite Assignment

Like class initializers, definite assignment of fields is enforced. Since a value never has a base class, the transition point to fully initialized is always implicit.