Instantiated.swift

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/// Marks a SafeDI dependency that is instantiated when its enclosing type is instantiated.
///
/// An example of the macro in use:
///
///     @Instantiated
///     private let dependency: DependencyType
///
/// Note that the access level of the dependency in the above example does not affect the dependency tree – a `private` dependency can still be `@Received` by `@Instantiable`-decorated types further down the dependency tree.
@attached(peer)
public macro Instantiated() = #externalMacro(module: "SafeDIMacros", type: "InjectableMacro")

/// Marks a SafeDI dependency that is instantiated when its enclosing type is instantiated.
///
/// Two examples of the macro in use:
///
///     @Instantiated(fulfilledByType: "ConcreteDependencyType")
///     private let dependency: TypeErasedDependencyType
///
///     @Instantiated(fulfilledByType: "ConcreteView", erasedToConcreteExistential: true)
///     private let dependencyBuilder: Instantiator<AnyView>
///
/// Note that the access level of the dependency in the above example does not affect the dependency tree – a `private` dependency can still be `@Received` by `@Instantiable`-decorated types further down the dependency tree.
///
/// - Parameters:
///   - concreteTypeName: The name of the concrete type that will be instantiated and assigned to this property. This parameter is only required when the decorated property’s type does not match an `@Instantiable` type or its `additionalTypes`. This parameter is particularly useful when working with a type-erased property.
///   - erasedToConcreteExistential: Whether the concrete type is being erased to a concrete existential type – a type that encapsulates a value conforming to a protocol without revealing the underlying type. Concrete type erasing types like `AnyView` fit this description. Set this parameter to `true` to encapsulate the created instance of `concreteTypeName` in a no-label initializer of the property’s type (e.g. `AnyView(ConcreteView())`).
///
///  - SeeAlso: [The Swift Programming Lanaguage’s explanation of existential types](https://docs.swift.org/swift-book/documentation/the-swift-programming-language/opaquetypes/#Boxed-Protocol-Types)
@attached(peer)
public macro Instantiated(
    fulfilledByType concreteTypeName: StaticString,
    erasedToConcreteExistential: Bool = false
) = #externalMacro(module: "SafeDIMacros", type: "InjectableMacro")