TreeScan

TreeScan[f,tree] evaluates f applied to the data of each subtree of tree in turn.

TreeScan[f,tree,levelspec] applies f to the data of subtrees on levels of tree specified by levelspec.

TreeScan[f,tree,levelspec->elems] applies f to the elements elems of subtrees on levels specified by levelspec.

TreeScan[f] represents an operator form of TreeScan that can be applied to a tree.

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