Path: utzoo!attcan!uunet!mcsun!ukc!edcastle!aiai!jeff From: jeff@aiai.ed.ac.uk (Jeff Dalton) Newsgroups: comp.lang.lisp Subject: Re: Common Lisp Package System Considered Harmful Message-ID: <3597@skye.ed.ac.uk> Date: 22 Oct 90 18:19:30 GMT References: Reply-To: jeff@aiai.UUCP (Jeff Dalton) Organization: AIAI, University of Edinburgh, Scotland Lines: 26 In article welch@sacral.cis.ohio-state.edu (Arun Welch) writes: >Yup, that's it. To give an example of how packages are so usefull, >look at Interlisp, which had no packages. The first function I ever defined in InterLisp-D redefined something in the editor. The function name I used was (if I recall correctly) DOT. However, it's worth noting that the designers of other Lisp dialects (eg, Scheme) do not seem to be planning to adopt Common Lisp's packages. Much of the Prolog community has also rejected that approach. (The so-called atom-based proposals for modules get so much criticism from some quarters that I don't think one could ever be adopted as standard.) And it's hard to see many other langauges doing it, because other languages usually don't have symbols as a datatype. Packages do have problems. Just for example: suppose you load in some code but forget to put in a required USE-PACKAGE. Well, all the symbols that ought to be USED-PACKAGE:SYM will be LOCAL-PACKAGE::SYM, and that's very hard to fix once it's happened. However, packages are a fairly good "pragmatic" solution in that they work fairly well and are available now, while the better Scheme solutions are still being developed.