JS Practice — Built-in Objects

Interface — Recursive Type

📖 Usage Example

interface TreeNode<T> {
  value: T
  children: TreeNode<T>[]
}
const root: TreeNode<number> = { value: 1, children: [] }

A recursive interface refers to itself, enabling tree and nested data structures.

Recursive Interfaces: Tree Node

An interface can reference itself, enabling recursive data structures.

Challenge: Implement createTreeNode<T>(value, children?) returning a TreeNode<T>.

createTreeNode(1)                // → { value: 1, children: [] }
createTreeNode(1, [createTreeNode(2)])  // → { value: 1, children: [{ value: 2, children: [] }] }

💡 Hints (1)

• Default parameter values are evaluated per call, so [] is safe here.