Construct an XDOC tree for a typewriter topic link directive @(tsee ...).
Macro:
(defmacro @tsee (&rest trees) (list '@tsee-fn (cons 'list trees)))
Function:
(defun @tsee-fn (trees) (declare (xargs :guard (tree-listp trees))) (make-tree-dir/&& :@tsee trees))
Theorem:
(defthm stringp-of-@tsee (equal (treep (@tsee-fn trees)) (tree-listp trees)))