AndyBowes

fun idSequence(seed:Int=0) : Sequence<Int>{
    return generateSequence(seed,{it + 1})
}

class TreeNode<T>(val id: T){
    val childNodes = mutableListOf<TreeNode<T>>()

    fun addChild(node: TreeNode<T>) = childNodes.add(node)
    fun removeChild(node: TreeNode<T>) = childNodes.remove(node)
    fun children() = childNodes.asIterable()