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,eda0a7cd6069ee4
X-Google-Attributes: gid103376,public
From: mgk25@cl.cam.ac.uk (Markus Kuhn)
Subject: Re: Type mess in Ada standard library
Date: 1999/07/21
Message-ID: <7n41v3$j6$1@pegasus.csx.cam.ac.uk>#1/1
X-Deja-AN: 503460683
References: <7n1uu4$so8$1@pegasus.csx.cam.ac.uk> <7n32tt$cio$1@nnrp1.deja.com>
Organization: U of Cambridge Computer Lab, UK
Newsgroups: comp.lang.ada
Date: 1999-07-21T00:00:00+00:00
List-Id: <comp.lang.ada>

Robert Dewar <robert_dewar@my-deja.com> writes:
|> It is definitely the case that it is occasionally annoying to
|> have to create named access types, when what you really want
|> is the anonymous access type created by an access parameter.
[...]
|> I would have liked to see an attribute, call it for now
|> 
|>   typ'Anonymous_Access
|> 
|> that created an anonymous access type to "typ". Indeed we
|> have discussed adding such an attribute to GNAT, particularly
|> for helping to solve the binding generation problem, where
|> such access types are common.

That sounds like a very good idea to me, and adding this in GNAT
would certainly be a valuable contribution. (It would be even nicer
if this were not a product-specific proprietary extension of the
language but part of the core language.)

Would it at the same time also be possible to add anonymous arrays?

  typ'Array(0..255,0..255)  -- anonymous 64k 2D array of typ
  typ'Array(<>,<>,<>)       -- any 3D array of typ

or something like that, which wherever they are used lead to identical
types iff the parameters are identical.

-- 
Markus G. Kuhn, Computer Laboratory, University of Cambridge, UK
Email: mkuhn at acm.org,  WWW: <http://www.cl.cam.ac.uk/~mgk25/>