workflowy

package collections import ( "iter" ) type TreeProvider[T any] interface { Node() T Children() iter.Seq[TreeProvider[T]] } type Tree[T any] struct { node T children []TreeProvider[T] } func (t *Tree[T]) Children() iter.Seq[TreeProvider[T]] { return iter.Seq[TreeProvider[T]](func(yield func(TreeProvider[T]) bool) { for _, child := range t.children { var treeProvider TreeProvider[T] = child if !yield(treeProvider) { break } } }) } func (t *Tree[T]) SetChildren(children []TreeProvider[T]) { t.children = children } func (t *Tree[T]) Node() T { return t.node } func NewTree[T any](node T, children []TreeProvider[T]) Tree[T] { return Tree[T]{node: node, children: children} } func CopyTree[T TreeProvider[T]](root T) Tree[T] { return copyTree(root) } func copyTree[T TreeProvider[T]](node T) Tree[T] { children := []TreeProvider[T]{} for child := range node.Children() { tree := copyTree(child.Node()) children = append(children, &tree) } return Tree[T]{node: node, children: children} }