Mystifier wrote:
> Thanks Aaron. You can find about Ruby at http://www.ruby-lang.org My
> VM is at http://vuby.berlios.de/ . Though nothing of vuby is yet on
> web, but I plan to have them shortly.
>
> I am considering to write VM in C++/C. Since Ruby shares a lot of
> features with lisp and small talk, I was interested in it. My major
> areas of importance was stack vs register based. What would be the best
> calling convention to be used. Do I use separate stacks for arguments
> and local variables ?
For many conventional languages (and Ruby counts as one such, I believe),
a single stack is sufficient. Parameters get pushed as part of the
evaluation of the function call; when you're inside the called function,
you address them stack (or frame) relative.
> In Ruby, we have lot of method calls (messaging) and I thought inlining
> them would be great.
For heavens sake, don't worry *now* about whether you should inline
things or not. *Especially* if you're using an interpreted VM. Get some
kind of minimal core working that you can experiment with.
All the performance speculation in the world is as nothing beside
measurements of real working systems. Write as much code as you can
*independantly* of which choices you make for method arguments/calls.
Then it's easy to see the effect of other choices. Even, with more
work, the effect of eliminating the option to ahve choices ...
--
Chris "electric hedgehog" Dollin
>From afranke@mathweb.org Tue Feb 1 08:47:51 2005
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From: afranke@mathweb.org
Newsgroups: comp.lang.pop
Subject: Re: Bug in poplog clisp: defclass :writer behaviour differs from
Date: Tue, 1 Feb 2005 08:47:51 +0000 (UTC)
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Aaron Sloman wrote:
> Could you send me a bit of lisp code to use for testing any such
> change please?
I have attached a test program; it's output should be self-explaining.
Btw, this is not a serious problem as it's easy to work around by using
accessors
(setf (a obj) val)
instead of writers, or alternatively by "ifdef"-ing for POPLOG:
#+POPLOG (setf (w obj) val)
#-POPLOG (w val obj)
But I haven't found a workaround for the 'let*' problem yet; using a
macro to transform it into deeply nested 'let's with a single assignment
each doesn't seem to help; the error stays the same. Ideas are welcome.
Cheers,
Andreas
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name="writer_test.lsp"
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filename="writer_test.lsp"
;;;
;;; Testing :writer arguments in defclass slots
;;;
(defun verbose (expr)
(format t "~S~%" expr)
(eval expr))
(format t "~%Defining test class c ...~%")
(verbose '(defclass c ()
((slot :accessor a :reader r :writer w))))
(defun test (f should-exist)
(format t " ~10A ..." f)
(let* ((exists (fboundp f))
(ok (equal exists should-exist)))
(if exists
(format t " is a defined function")
(format t " is undefined"))
(if ok
(format t " (ok)~%")
(format t " (*** NOT OK ***)~%"))))
(format t "~%Testing :accessor a ...~%")
(test 'a t)
(test '(setf a) t)
(format t "~%Testing :reader r ...~%")
(test 'r t)
(test '(setf r) nil)
(format t "~%Testing :writer w ...~%")
(test 'w t)
(test '(setf w) nil)
(format t "~%Creating test object o ...~%")
(verbose '(setq o (make-instance 'c)))
(format t "~%Trying to use :writer function w directly:~%")
(verbose '(w 42 o))
(format t " ... succeeded. (r o) = ~S~%" (r o))
#+POPLOG (bye)
#-POPLOG (quit)
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