Path: utzoo!utgpu!attcan!uunet!cs.utexas.edu!oakhill!dover!hume From: hume@buckwheat.sps.mot.com (Chris Hume) Newsgroups: comp.lang.lisp Subject: Managing Package Dependencies Message-ID: Date: 28 Sep 89 19:28:35 GMT Sender: news@dover.sps.mot.com Distribution: comp Lines: 48 Thanks Dan, for your careful explanation. The idea of a [kernel] package in which a particular design organization's interfaces can find a common "home" actually bears some similarity to my idea of having a "standard" (or perhaps better, a "default") package for (generic interface) symbols. Package conflicts will still arise, where products from independent design organizations are "used together", the resolution of which might be expedited by some level of convention for "kernel" package organization. My package ignorance confusion arose because it had not occurred to me that DEFMETHOD in a private package would use a symbol from some other package (in implicit use). This should have been obvious, but it may suggest that Users will have some difficulty maintaining consistent "package dependency" across modules that specify either interfaces (via DEFGENERIC), their method, and their application. The handy self-referential acronym documented in CLtL: "Put IN Seven EXtremely Random USEr Interface COmmands" may introduce EXPORT prematurely. To handle the case we have been discussing (exporting a symbol one might incidentally inherit from another package) it seems natural to move EXPORT below USE-PACKAGE (and probably also IMPORT). CLtL Recommendation Alternative Order ------------------- ----------------- PROVIDE PROVIDE IN-PACKAGE IN-PACKAGE SHADOW SHADOW EXPORT REQUIRE REQUIRE USE-PACKAGE USE-PACKAGE IMPORT IMPORT EXPORT [Either ordering may be modulated by introduction of "File Attributes".] There are no doubt considerations (other than lack of a handy self- referential acronym) that this alternative overlooks. As a separate topic I would like to understand the rationale behind distinguishing module dependency from package dependency. Can anyone characterize the current state of standardization for the concept (and support) of "systems"? Chris -- Phone: (602) 994-6835 EMail: hume@sps.mot.com