Common Lisp solved this problem 20 years ago Alan Watson (25 Oct 2005 11:02 UTC)
Re: Common Lisp solved this problem 20 years ago Marcin 'Qrczak' Kowalczyk (25 Oct 2005 19:11 UTC)
Re: Common Lisp solved this problem 20 years ago Per Bothner (25 Oct 2005 19:22 UTC)
Re: Common Lisp solved this problem 20 years ago Alan Watson (25 Oct 2005 20:11 UTC)
Re: Common Lisp solved this problem 20 years ago Alan Watson (25 Oct 2005 20:12 UTC)
Re: Common Lisp solved this problem 20 years ago Marcin 'Qrczak' Kowalczyk (25 Oct 2005 22:08 UTC)
Re: Common Lisp solved this problem 20 years ago Alan Watson (25 Oct 2005 20:28 UTC)
Re: Common Lisp solved this problem 20 years ago Alan Watson (25 Oct 2005 20:22 UTC)
Re: Common Lisp solved this problem 20 years ago Aubrey Jaffer (25 Oct 2005 21:54 UTC)
Re: Common Lisp solved this problem 20 years ago Alan Watson (25 Oct 2005 22:23 UTC)
Re: Common Lisp solved this problem 20 years ago Aubrey Jaffer (26 Oct 2005 02:25 UTC)
Re: Common Lisp solved this problem 20 years ago Alan Watson (26 Oct 2005 03:52 UTC)
Re: Common Lisp solved this problem 20 years ago Per Bothner (26 Oct 2005 05:46 UTC)
Re: Common Lisp solved this problem 20 years ago Taylor Campbell (26 Oct 2005 20:05 UTC)
Re: Common Lisp solved this problem 20 years ago John.Cowan (26 Oct 2005 20:12 UTC)
Re: Common Lisp solved this problem 20 years ago Per Bothner (26 Oct 2005 20:38 UTC)
Re: Common Lisp solved this problem 20 years ago Thomas Bushnell BSG (26 Oct 2005 21:53 UTC)
Re: Common Lisp solved this problem 20 years ago Per Bothner (26 Oct 2005 22:13 UTC)
Re: Common Lisp solved this problem 20 years ago Thomas Bushnell BSG (26 Oct 2005 22:20 UTC)
Re: Common Lisp solved this problem 20 years ago Alan Watson (26 Oct 2005 23:31 UTC)
Re: Common Lisp solved this problem 20 years ago Per Bothner (27 Oct 2005 00:20 UTC)
Re: Common Lisp solved this problem 20 years ago Thomas Bushnell BSG (27 Oct 2005 03:20 UTC)
Re: Common Lisp solved this problem 20 years ago Per Bothner (27 Oct 2005 05:52 UTC)
Re: Common Lisp solved this problem 20 years ago Taylor Campbell (26 Oct 2005 23:51 UTC)
Re: Common Lisp solved this problem 20 years ago Per Bothner (27 Oct 2005 00:14 UTC)
Re: Common Lisp solved this problem 20 years ago Thomas Bushnell BSG (27 Oct 2005 03:21 UTC)
Re: Common Lisp solved this problem 20 years ago Per Bothner (27 Oct 2005 05:41 UTC)
Re: Common Lisp solved this problem 20 years ago Thomas Bushnell BSG (26 Oct 2005 21:52 UTC)
Re: Common Lisp solved this problem 20 years ago John.Cowan (26 Oct 2005 22:14 UTC)
Re: Common Lisp solved this problem 20 years ago Thomas Bushnell BSG (26 Oct 2005 22:17 UTC)
Re: Common Lisp solved this problem 20 years ago Alan Watson (26 Oct 2005 06:15 UTC)
Re: Common Lisp solved this problem 20 years ago Per Bothner (26 Oct 2005 06:51 UTC)
Re: Common Lisp solved this problem 20 years ago Alan Watson (26 Oct 2005 07:15 UTC)
Re: Common Lisp solved this problem 20 years ago Per Bothner (26 Oct 2005 07:38 UTC)
Re: Common Lisp solved this problem 20 years ago Alan Watson (26 Oct 2005 07:49 UTC)
Re: Common Lisp solved this problem 20 years ago Marcin 'Qrczak' Kowalczyk (26 Oct 2005 09:09 UTC)

Re: Common Lisp solved this problem 20 years ago Alan Watson 26 Oct 2005 23:30 UTC

I don't like the Kawa "coercion" semantic for type declarations; I don't
think it is wrong per se, but I much prefer Common Lisps "assertion"
semantics. That is, in Common Lisp, if I declare that a variable has a
certain type, the compiler can do just about anything, provided the
program works correctly when the variable has that type. Common
behaviours are:

(a) Doing nothing.

(b) Complaining if the variable does not have that type.

(c) Assuming that the variable has that type and and acting in a way
that will be dangerous if it does not.

These are often offered as compilation options. They seem to offer a
wider range of useful behaviour and a wider range of trade-offs between
safety and optimization.

The "assertion" semantics also more naturally extend to limited ranges
(e.g., asserting that an integer is non-zero) or using unions of types.

Regards,

Alan
--
Dr Alan Watson
Centro de Radioastronomía y Astrofísica
Universidad Astronómico Nacional de México