You are looking at historical revision 40162 of this page. It may differ significantly from its current revision.
tree
This is an implementation of John Cowan's tree library with the following additional procedures added.
tree-find
(tree-find pred tree default)
Walks the tree in preorder and exits out early when a node (a subtree or atom) matches pred. Returns the first matching node, not a copy but the real one. If there is on match, return default, which is a mandatory argument.
tree-find-equal?
(tree-find-equal? tree needle)
Like tree-find, but finds the first node that's equal? to the needle or returns #f as a default.
The reason you might need that is because many of the other operations in the library act on subtrees, not copies of subtrees. So this is a way for you to turn a copy into a reference to the original subtree.
tree-atoms-any?
(tree-atoms-any? pred tree)
Like tree-any?, but only consider atoms.
tree-atoms-every?
(tree-atoms-every? pred tree)
Like tree-every?, but only consider atoms.
tree-remove
(tree-remove pred tree)
Remove every node (whether subtrees or atoms) that matches pred.