ErasedInstantiator.swift

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/// A SafeDI dependency designed for the deferred instantiation of a type-erased instance of a
/// type decorated with `@Instantiable`.
///
/// - SeeAlso: `Instantiator`
/// - SeeAlso: `SendableInstantiator`
/// - SeeAlso: `SendableErasedInstantiator`
public final class ErasedInstantiator<ForwardedProperties, Instantiable> {
    /// - Parameter instantiator: A closure that takes `ForwardedProperties` and returns an instance of `Instantiable`.
    public init(_ instantiator: @escaping (ForwardedProperties) -> Instantiable) {
        self.instantiator = instantiator
    }

    /// - Parameter instantiator: A closure that returns an instance of `Instantiable`.
    public init(_ instantiator: @escaping () -> Instantiable) where ForwardedProperties == Void {
        self.instantiator = { _ in instantiator() }
    }

    /// Instantiates and returns a new instance of the `@Instantiable` type, using the provided arguments.
    ///
    /// - Parameter arguments: Arguments required for instantiation.
    /// - Returns: An `Instantiable` instance.
    public func instantiate(_ arguments: ForwardedProperties) -> Instantiable {
        instantiator(arguments)
    }

    /// Instantiates and returns a new instance of the `@Instantiable` type.
    ///
    /// - Returns: An `Instantiable` instance.
    public func instantiate() -> Instantiable where ForwardedProperties == Void {
        instantiator(())
    }

    private let instantiator: (ForwardedProperties) -> Instantiable
}