Subject: Re: DECLARE, DECLAIM and PROCLAIM that I'm not sure I understand the difference!
From: Erik Naggum <clerik@naggum.no>
Date: 1998/03/20
Newsgroups: comp.lang.lisp
Message-ID: <3099416301467097@naggum.no>


* Steven D. Majewski
| PROCLAIM is clearly global. 
| The distinction for DECLAIM seems a bit fuzzy to me.

  PROCLAIM is a function that the compiler does not recognize in any
  special way.  DECLAIM is a macro that (effectively) expands into a
  PROCLAIM at compile-time if it occurs at toplevel.

| Is this because it's meant for the compiler and it really
| means: "it depends on how your compiler wants to handle it" ? 

  no, the semantics is clearly defined.  effectively,

(declaim (optimize speed))

  is the same as

(eval-when (:compile-toplevel :load-toplevel :execute)
  (proclaim '(optimize speed)))

  the only thing I would wish for is that DECLAIM had no effect when
  loading.  loading a file with DECLAIM often introduces declarations that
  are not wanted at load-time, like OPTIMIZE settings.

  the consequence of this is that one has to wrap the proclamation in
  (EVAL-WHEN (:COMPILE-TOPLEVEL) ...) and this sort of defeats the purpose
  of having DECLAIM in the first place, IMHO.  an obvious counter-measure
  is to include OPTIMIZE settings in every file that is to be compiled.

  I wonder how the global declarations were intended to be used.

#:Erik
-- 
  religious cult update in light of new scientific discoveries:
  "when we cannot go to the comet, the comet must come to us."