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From: ncohen@watson.ibm.com (Norman H. Cohen)
Subject: Re: Access-To-Object-Type question.
Date: 1996/04/25
Message-ID: <4lntl6$hpj@watnews1.watson.ibm.com>#1/1
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distribution: world
references: <317EEBB4.5C18@chicago.aae.com>
organization: IBM T.J. Watson Research Center
reply-to: ncohen@watson.ibm.com
newsgroups: comp.lang.ada
Date: 1996-04-25T00:00:00+00:00
List-Id: <comp.lang.ada>

In article <317EEBB4.5C18@chicago.aae.com>, Frank Falk
<falk@chicago.aae.com> writes: 

|> I am reading Ada As a Second Language, second edition and have a
|> question about section 8.3, Access-To-Object-Type Declarations.
|> What is the purpose of these?  Can someone give me an example?

Keep reading.  Section 8.5, "The Use of Access Types," gives 16 pages of
examples.

|> It looks like I'm declaring pointers to variables declared in the
|> same location.

I assume that by "in the same location" you mean in the same piece of Ada
code.  The short fragments in Section 8.3 are just there to show you what
access types can and cannot point to, and when constructs such as X.all
can be used as constants and as variables.  They do not illustrate the
typical use of access types in programs.  (The examples in Section 8.5 do
that.)  In typical uses, it is not known at the point at which an
access value is used that it points to a particular object.

--
Norman H. Cohen    ncohen@watson.ibm.com