Update VariadicView

Sources/OpenSwiftUI/Core/View/VariadicView/ForEach.swift

@@ -0,0 +1,54 @@
+//
+//  ForEach.swift
+//  OpenSwiftUI
+//
+//  Audited for RELEASE_2021
+//  Status: WIP
+
+/// A structure that computes views on demand from an underlying collection of
+/// identified data.
+///
+/// Use `ForEach` to provide views based on a
+/// [RandomAccessCollection](https://developer.apple.com/documentation/swift/randomaccesscollection)
+/// of some data type. Either the collection's elements must conform to
+/// [Identifiable](https://developer.apple.com/documentation/swift/identifiable) or you
+/// need to provide an `id` parameter to the `ForEach` initializer.
+///
+/// The following example creates a `NamedFont` type that conforms to
+/// [Identifiable](https://developer.apple.com/documentation/swift/identifiable), and an
+/// array of this type called `namedFonts`. A `ForEach` instance iterates
+/// over the array, producing new ``Text`` instances that display examples
+/// of each OpenSwiftUI ``Font`` style provided in the array.
+///
+///     private struct NamedFont: Identifiable {
+///         let name: String
+///         let font: Font
+///         var id: String { name }
+///     }
+///
+///     private let namedFonts: [NamedFont] = [
+///         NamedFont(name: "Large Title", font: .largeTitle),
+///         NamedFont(name: "Title", font: .title),
+///         NamedFont(name: "Headline", font: .headline),
+///         NamedFont(name: "Body", font: .body),
+///         NamedFont(name: "Caption", font: .caption)
+///     ]
+///
+///     var body: some View {
+///         ForEach(namedFonts) { namedFont in
+///             Text(namedFont.name)
+///                 .font(namedFont.font)
+///         }
+///     }
+///
+/// ![A vertically arranged stack of labels showing various standard fonts,
+/// such as Large Title and Headline.](OpenSwiftUI-ForEach-fonts.png)
+public struct ForEach<Data, ID, Content> where Data: RandomAccessCollection, ID: Hashable {
+
+    /// The collection of underlying identified data that OpenSwiftUI uses to create
+    /// views dynamically.
+    public var data: Data
+
+    /// A function to create content on demand using the underlying data.
+    public var content: (Data.Element) -> Content
+}

Sources/OpenSwiftUI/Core/View/VariadicView/VariadicView_Children.swift

@@ -1,6 +1,69 @@
-// TODO
+//
+//  VariadicView_Children.swift
+//  OpenSwiftUI
+//
+//  Audited for RELEASE_2021
+//  Status: TODO
+//  ID: 52A2FFECFBCF37BFFEED558E33EBD1E3
+
+internal import OpenGraphShims
 
 /// An ad hoc collection of the children of a variadic view.
 public struct _VariadicView_Children {
+    var list: ViewList
+    var contentSubgraph: OGSubgraph
+}
+
+extension _VariadicView_Children: RandomAccessCollection {
+    public struct Element: PrimitiveView, UnaryView, Identifiable {
+
+//        var view: _ViewList_View
+        var traits: ViewTraitCollection
+
+        public var id: AnyHashable {
+//            view.viewID
+            fatalError("TODO")
+
+        }
+        public func id<ID>(as _: ID.Type = ID.self) -> ID? where ID : Hashable {
+            fatalError("TODO")
+        }
+
+        public subscript<Trait: _ViewTraitKey>(key: Trait.Type) -> Trait.Value {
+            get { traits[key] }
+            set { traits[key] = newValue }
+        }
+
+        public static func _makeView(view: _GraphValue<_VariadicView_Children.Element>, inputs: _ViewInputs) -> _ViewOutputs {
+            fatalError("TODO")
+        }
+    }
 
+    public var startIndex: Int {
+        fatalError("TODO")
+
+//      get
+    }
+    public var endIndex: Int {
+        fatalError("TODO")
+
+//      get
+    }
+    public subscript(index: Int) -> _VariadicView_Children.Element {
+        fatalError("TODO")
+
+//      get
+    }
+}
+
+extension _VariadicView_Children {
+    private struct Child: Rule, AsyncAttribute {
+        typealias Value = ForEach<_VariadicView_Children, AnyHashable, _VariadicView_Children.Element>
+
+        @Attribute var children: _VariadicView_Children
+
+        var value: Value {
+            fatalError("TODO")
+        }
+    }
 }

Sources/OpenSwiftUI/Core/View/VariadicView/VariadicView_ViewRoot.swift

@@ -4,6 +4,7 @@
 //
 //  Audited for RELEASE_2021
 //  Status: WIP
+//  ID: 00F12C0E37A19C593ECA0DBD3BE26541
 
 internal import OpenGraphShims
 

Sources/OpenSwiftUI/Core/View/ViewList/ViewListInputs.swift

@@ -12,8 +12,7 @@ public struct _ViewListInputs {
     private var base: _GraphInputs
     var implicitID: Int
     var options: _ViewListInputs.Options
-    @OptionalAttribute
-    var traits: ViewTraitCollection?
+    @OptionalAttribute var traits: ViewTraitCollection?
     var traitKeys: ViewTraitKeys?
 
     struct Options: OptionSet {

Sources/OpenSwiftUI/Core/View/ViewList/ViewList_ID.swift

@@ -0,0 +1,12 @@
+//  ID: 70E71091E926A1B09B75AAEB38F5AA3F
+
+struct _ViewList_ID {
+    var _index: Int32
+    var implicitID: Int32
+    private var explicitIDs: [Explicit]
+}
+
+extension _ViewList_ID {
+    private struct Explicit {
+    }
+}

Sources/OpenSwiftUI/Core/View/ViewList/ViewList_View.swift

@@ -0,0 +1,9 @@
+internal import OpenGraphShims
+
+struct _ViewList_View {
+    var elements: _ViewList_Elements
+    var id: _ViewList_ID
+    var index: Int
+    var count: Int
+    var contentSubgraph: OGSubgraph
+}

Sources/OpenSwiftUI/Core/View/ViewTrait/ViewTraitKey.swift

@@ -5,7 +5,7 @@
 //  Audited for RELEASE_2021
 //  Status: Complete
 
-protocol _ViewTraitKey {
+public protocol _ViewTraitKey {
     associatedtype Value
     static var defaultValue: Value { get }
 }