Make graph expressible by dictionary- and array literals

Author: flowtoolz

Code/Graph+CreateAndAccess/Graph+ConvenientInitializers.swift

@@ -1,3 +1,27 @@
+//extension Graph: ExpressibleByArrayLiteral where NodeValue: Identifiable, NodeValue.ID == NodeID
+//{
+//    public init(arrayLiteral elements: NodeValue...)
+//    {
+//        self.init(values: elements)
+//    }
+//}
+
+extension Graph: ExpressibleByArrayLiteral where NodeID == NodeValue
+{
+    public init(arrayLiteral elements: NodeValue...)
+    {
+        self.init(values: elements)
+    }
+}
+
+extension Graph: ExpressibleByDictionaryLiteral
+{
+    public init(dictionaryLiteral elements: (NodeID, NodeValue)...)
+    {
+        self.init(idValuePairs: elements)
+    }
+}
+
 public extension Graph
 {
     init(values: some Sequence<NodeValue>)

README.md

@@ -221,7 +221,7 @@ SwiftNodes is already being used in production, but [Codeface](https://codeface.
 ## Roadmap
 
 1. Further align API with official Swift data structures (What would Apple do?):
-   1. Add the usual suspects of applicable protocol conformances (`Sequence`/`Collection`, expressibility by literals, etc.)
+   1. Add the usual suspects of applicable protocol conformances (`Sequence`/`Collection`)
    2. Compare with- and learn from API and implementation of [Swift Collections](https://github.com/apple/swift-collections)
 2. Round out and add algorithms (starting with the needs of Codeface):
    1. Make existing algorithms compatible with cyclic graphs (two of them are still not)