Subject: Re: Midfunction Recursion From: Erik Naggum <firstname.lastname@example.org> Date: 24 Oct 2002 18:42:10 +0000 Newsgroups: comp.lang.lisp Message-ID: <email@example.com> * Steven E. Harris <firstname.lastname@example.org> | It's not yet intuitively evident to me, but I'd like to get to the point | where it is. I consulted the HyperSpec on DO and found this clause: Investigate what the standard has to say on /bindings/. | If so, how could one force the capture of the current value of /i/ to | eventually present (4 3 2 1)? As you would capture any other value in a closure, create a binding and a closure over it. E.g., to return a function that captures a binding: (let ((x <initial>)) (lambda (&optional (new nil new-p)) (if new-p (setq x new) x)))) Call the returned function with a value to set the value of the binding, with no value to return the initial or last set value. A more Common Lisp way to do the same would be (let ((x <initial>)) (defun x () x) (defun (setf x) (new) (setq x new))) -- Erik Naggum, Oslo, Norway Act from reason, and failure makes you rethink and study harder. Act from faith, and failure makes you blame someone and push harder.