From mboxrd@z Thu Jan  1 00:00:00 1970
X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me
X-Spam-Level: 
X-Spam-Status: No, score=-1.3 required=5.0 tests=BAYES_00,INVALID_MSGID
	autolearn=no autolearn_force=no version=3.4.4
X-Google-Language: ENGLISH,ASCII-7-bit
X-Google-Thread: 103376,eac70c5fad02d925
X-Google-Attributes: gid103376,public
From: ok@goanna.cs.rmit.edu.au (Richard A. O'Keefe)
Subject: Re: Concerning subscript bounds checks
Date: 1996/07/02
Message-ID: <4ra3p1$b0f@goanna.cs.rmit.edu.au>#1/1
X-Deja-AN: 163219261
references: <4qdj3e$btf@goanna.cs.rmit.EDU.AU>
 <4ql9eq$hdt@goanna.cs.rmit.EDU.AU> <4r1aep$7ga@natasha.rmii.com>
 <4r7r65$nj@goanna.cs.rmit.EDU.AU> <Dtv6A6.B5K@world.std.com>
organization: Comp Sci, RMIT, Melbourne, Australia
keywords: subscripts
newsgroups: comp.lang.ada
nntp-posting-user: ok
Date: 1996-07-02T00:00:00+00:00
List-Id: <comp.lang.ada>


I wrote:
	type Coord is ...
	type Point is array (Coord) of Float;
	    let J be Simplex_Range'Val(
		Point'Range'Pos(I) - Point'Range'Pos(Point'Range'First))
  However, I couldn't figure out any way to code that conversion from I to J.
  (The immediate problem is that Point'Range is a _range_, not a _(sub)type_,
  so Point'Range'Pos is inexpressible.)

bobduff@world.std.com (Robert A Duff) writes:

>What's wrong with "Coord'Pos(I) - Coord'Pos(Point'First)"?

I think it was probably too obvious.
For some reason, I didn't want to use the name of the index type.
I can no longer recall why.

-- 
Fifty years of programming language research, and we end up with C++ ???
Richard A. O'Keefe; http://www.cs.rmit.edu.au/~ok; RMIT Comp.Sci.