Re: Function result

[jsa@alexandria.organon.com (Jon S Anthony)]

In article <5os5r8$4ud@netline.jpl.nasa.gov> vsnyder@gyre.jpl.nasa.gov (Van Snyder) writes:

> pass the address where the function result is to land as a "hidden argument."
> In this way, the syntactic device of assigning to the function result
> _really_is_ assigning directly to the function result -- no extra copying
> involved.
> 
> By the way, this would eliminate the problem about returning a limited
> type in Ada.

????  What problem is that???


> 1.  The client is expected to supply the address where the function result
>     is desired as a "hidden argument".

Sounds like a procedure with an out parameter...


> 3.  Since there's no copying going on outside the function, it would be OK
>     to allow returning a limited type.

There's no problem in returning a limited type.  I do it all the time.
What do mean here???


> 4.  In the function, the result would be materialized by storing into the
>     result variable, not by mentioning the value in a "return" statement.

Well, this _WOULD_ seem to cause a problem with returning limited
types, as it would require assignment.


/Jon
-- 
Jon Anthony
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