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From: kassover@minerva.crd.ge.com (David Kassover)
Newsgroups: comp.lang.ada
Subject: Re: limited private types, "=" operator
Message-ID: <10687@crdgw1.crd.ge.com>
Date: 2 Aug 90 17:46:36 GMT
References: <1152@cs.nps.navy.mil>
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List-Id: <comp.lang.ada>

In article <1152@cs.nps.navy.mil> erickson@cs.nps.navy.mil (David Erickson) writes:
|Is there any way to define "=" for a limited private type which is an
|access type (which may be null)?  The problem arises trying to test for
|null without producing an infinitely recursive definition.
|
|The only solution that I am aware of is to use UNCHECKED_CONVERSION to
|retype the access type during the test for null, but this is a hack.
|Is there a cleaner solution?
|

Export from the package defining the limited type a function that
returns TRUE if the access type variable is not null.  Or the other way
around, if you prefer.

--
David Kassover             "Proper technique helps protect you against
kassover@ra.crd.ge.com	    sharp weapons and dull judges."
kassover@crd.ge.com			F. Collins