Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Path: utzoo!utgpu!water!watmath!clyde!rutgers!husc6!bu-cs!bzs
From: bzs@bu-cs.UUCP
Newsgroups: comp.lang.c
Subject: Re: Standard int sizes
Message-ID: <6588@bu-cs.BU.EDU>
Date: Wed, 15-Apr-87 18:10:01 EST
Article-I.D.: bu-cs.6588
Posted: Wed Apr 15 18:10:01 1987
Date-Received: Fri, 17-Apr-87 03:45:23 EST
References: <6759@brl-adm.ARPA> <230@ems.UUCP> <170@vianet.UUCP> <3286@pogo.TEK.COM> <103@buengc.BU.EDU>
Distribution: na
Organization: Boston U. Comp. Sci.
Lines: 46
In-reply-to: shaun@buengc.BU.EDU's message of 15 Apr 87 22:01:30 GMT
Posting-Front-End: GNU Emacs 18.41.4 of Mon Mar 23 1987 on bu-cs (berkeley-unix)


It seems clear to me that if there is to be any alternate approach to
declaring portable integer sizes then Pascal (lord forgive me) had the
right approach. Let the programmer declare a range and then let that
be resolved automatically in a machine independant way:

	int foo range {-10000..10000};

And forget about how many bits/bytes are needed as you're not sure
what the right thing is anyhow in advance. This proposal involves
saying exactly what you mean.

Too much trouble to specify a range? Not known in advance? Ooops,
you got bugs (or you're always defaulting to max.)

This could probably be handled adequately by a simple C
pre-pre-processor which picked up the ranges and replaced them with
the appropriate declarations, I could imagine:

	INT(-10000,10000) foo, bar;
	INT(0,255) baz;

as an easily parsed syntax, although not terribly aesthetic. Perhaps
doing it as psuedo-typedefs would be superior:

#TYPEDEF int with range {-10000,10000} medium_int
#TYPEDEF int with range {0,255} small_int

	...

	medium_int foo, bar;
	small_int baz;

You can almost do this with the pre-processor but it's hard to nest
#if's intelligently into #defines (maybe someone has an idea.)  The
important thing is looking at the range specs and deciding
intelligently which is the best type to use. Just defining a bunch of
small_int defines is not powerful enough (tho I'd love to be convinced
otherwise, it would simplify this.) The output would be normal
typedefs.

Note that this, I claim, solves the range problem in a portable way
without requiring any modification in the language definition, just
a utility (in the spirit of YACC or LEX.)

	-Barry Shein, Boston University