Re: No to CL packages

[Richard Stallman <rms@gnu.org>]

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  > I see no need to invent yet another package system.

We already have it, not quite finished.

  > > With that, we will be able to implement packages that work reliably
  > > and without ambiguities.

  > You mention reliability and ambiguity.  What do you mean, in a concrete
  > example?

I can't write an example of Common Liso packages -- it was 40 years
ago that I implemented them for the Lisp Machine.  But I recall what
the unreliability was.  With CL packages, the reader searched a list
of packages (specified by the current package) for a symbol with the
name just read.  This means that the unexpected presence of a symbol
with that name, in an early package in the list, could alter the
meaning.

If the list includes packages foo abd bar, and you write `my-hack'
expecting the symbol to be found in bar, but unexpectedly foo contains
a symbol named my-hack, you will get that one.

  > In case you're thinking in terms of the pre-CL package system that some
  > Lisp machines had in the 80s, please read chapter 11 of "Common Lisp the
  > Language 2nd edition" by Guy Steele.  CL's package system is not like
  > the older one.

I implemented packages according to the CL specifications.  Perhaps
the specifications for packages have been changed since then.  I'm
willing to look at that.

Being hundreds of messages backlogged from the past 10 days, I'd
rather not try to download the whole CL specs and search through them.
Would you please email me that specific chapter?

-- 
Dr Richard Stallman (https://stallman.org)
Chief GNUisance of the GNU Project (https://gnu.org)
Founder, Free Software Foundation (https://fsf.org)
Internet Hall-of-Famer (https://internethalloffame.org)