Copying by dispatching on remote access to class wide types

["Kevin Rigotti" <rigotti@atc.dera.gov.uk>]

What I would like to be able to do is have a function to take a local copy
of part of some remote data, of the form

    function copy(remote : Distributed_Object_T; .... ) return
Distributed_Object_T

where calls dispatch on the controlling operand "remote" which would be a
derefence of a remote access to class wide type, and NOT on the returned
value (of variable size as determined by the other arguments) which is a
local copy of part of the remote data.

This isn't valid Ada (is it?) and would get complaints about trying to
dispatch twice in one call.

I can see that one way of achieving what I want would be by associating the
Distributed Object with some other class that would accept the dispatching
call and use a supplied access value to return the data, but I can't help
feeling that I am getting myself into a bit of mess when there is probably a
perfectly straight forward way of doing it.

Suggestions?

Kevin
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