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Date: 4 May 93 22:13:55 GMT
From: widget!jgg@uunet.uu.net  (John Goodsen)
Subject: Re: Passing procedures as parameters to procedures.
Message-ID: <1993May4.221355.13487@evb.com>
List-Id: <comp.lang.ada>

In article <1993May3.190746.1043@ee.ubc.ca> luisl@ee.ubc.ca (luis linares-rojas
) writes:
>Subject: Procedures/functions as parameters to procedures/functions.
>Before commiting myself to any long term commitment with the Ada language,
>I've been revising its capabilities.  There is something that I have not
>found so far: how to pass a procedure (or a function) as a parameter to anothe
r
>procedure (or function).  Or, in the same spirit, how to create an array of
>procedures.  The question is: is there a way of doing this in Ada, and (if so)
>how?  I'd appreciate any help.

If you can't wait for Ada 9X and you need dynamic binding of 
the procedure to call, then you might also check out how it's
currently done in the Xt/Motif bindings which support call by
address of Ada procedures from C.  Basically, you 
pass the address of an Ada procedure to an external routine 
using the 'ADDRESS attribute and have that routine call the Ada routine 
that was passed to it.  Of course, this has the usual side effects 
of being compiler dependent, etc... but it works in Ada 83.

As was pointed out in a previous reply,  you'll have this in Ada 9X,
if you can wait that long.


-- 
John Goodsen                EVB Software Engineering, Inc.
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