Path: utzoo!attcan!uunet!mcvax!ukc!icdoc!qmc-cs!harlqn!andrew From: andrew@jung.harlqn.uucp (Andrew Watson) Newsgroups: comp.lang.lisp Subject: CLOS availability (was Re: Common Lisp on the DEC 3100) Message-ID: Date: 29 Jul 89 17:17:53 GMT References: <162@mit-amt.MEDIA.MIT.ErU> <15627@pasteur.Berkeley.EDU> Sender: news@harlqn.UUCP Organization: Harlequin Limited, Cambridge, UK Lines: 42 In-reply-to: faustus@dogwood.Berkeley.EDU's message of 20 Jul 89 19:45:31 GMT In article <15627@pasteur.Berkeley.EDU> faustus@dogwood.Berkeley.EDU (Wayne A. Christopher) writes: Also, I'm interested in running CLOS. What experience have people had with the efficiency of this system? The book says it can be done very efficiently, but I've heard people say it's a dog, in both speed and memory usage. Well, of course, there is no one CLOS implementation - just a CLOS spec. The most widespread implementation is PCL, which is publicly available, but isn't quite conformant to Chapters 1 & 2 of the CLOS spec (yet). We at Harlequin have implemented our own CLOS which does conform to Chapters 1 & 2. The trick to getting a fast CLOS implementation is to exploit the strengths of your compiler, so that the critical things like method dispatch and slot access have good performance. I expect that as CLOS takes hold in the Lisp world, we will see more CLOS implementations closely tied into particular Lisp compilers for this reason. Gathering objective (no pun intended!) data on CLOS performance is difficult, since there aren't any widely used benchmarks, but we have used CLOS extensively with CLUE, as the implementation language for our window toolkit built on CLUE, and throughout the LispWorks programming environment generally. We're happy with the resulting performance. Who has the best implementation of CLOS? If I gave you my opinion on that, it'd be advertising (:-). Thanks in advance, Wayne -- Regards, Andrew. +-----------------------------------------------------------------------------+ | Andrew Watson, andrew@uk.co.harlqn -or- | | Harlequin Limited, mcvax!ukc!harlqn!andrew | | Barrington Hall, Barrington, Tel: +44 223 872522 | | Cambridge CB2 5RG, UK Fax: +44 223 872519 | +-----------------------------------------------------------------------------+