wip

Sources/CliDoc2/TextNode.swift

@@ -0,0 +1,61 @@
+public protocol NodeRepresentable {
+  func render() -> String
+}
+
+public protocol TextNode: NodeRepresentable {
+  // swiftlint:disable type_name
+  associatedtype _Body: TextNode
+  typealias Body = _Body
+  // swiftlint:enable type_name
+
+  var body: Body { get }
+}
+
+public extension TextNode {
+  func render() -> String {
+    body.render()
+  }
+}
+
+extension String: NodeRepresentable {
+  public func render() -> String {
+    self
+  }
+}
+
+extension String: TextNode {
+  public var body: some TextNode {
+    self
+  }
+}
+
+public struct AnyTextNode: TextNode {
+  let makeString: () -> String
+
+  public init<N: TextNode>(_ node: N) {
+    self.makeString = node.render
+  }
+
+  public var body: some TextNode { makeString() }
+}
+
+public extension TextNode {
+  func eraseToAnyTextNode() -> AnyTextNode {
+    AnyTextNode(self)
+  }
+}
+
+extension Optional: TextNode where Wrapped: TextNode {
+  public var body: some TextNode {
+    guard let node = self else { return "".eraseToAnyTextNode() }
+    return node.eraseToAnyTextNode()
+  }
+}
+
+extension Optional: NodeRepresentable where Wrapped: NodeRepresentable {
+
+  public func render() -> String {
+    guard let node = self else { return "" }
+    return node.render()
+  }
+}