//// NodeKind
///// Tree node kind.
#[derive(Clone, Copy, Debug, Eq, PartialEq)]pubenumNodeKind{/// A branch is a node that can have children.
Branch,/// A leaf is a node that cannot have children.
Leaf,}implNodeKind{/// Whether the node is a branch.
pubfnis_branch(&self)->bool{matches!(self,Self::Branch)}/// Whether the node is a leaf.
pubfnis_leaf(&self)->bool{matches!(self,Self::Leaf)}}