- descend-focused stop-predicate treeprocedure
Descends the focused containers of the given TREE, stopping at the first container which satisfies STOP-PREDICATE.
- Processing stops when this predicate first returns true. The return value is the container with which this predicate was evaluated.
- (Part of) a list of containers as returned by (tree).
(define (descend-focused stop-predicate tree) (if (stop-predicate tree) tree (if (null? (alist-ref 'focus tree)) tree (descend-focused stop-predicate (let ((focused-id (first (alist-ref 'focus tree)))) (find (lambda (con) (= (alist-ref 'id con) focused-id)) (append (alist-ref 'nodes tree) (alist-ref 'floating_nodes tree))))))))