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From: Simon Wright <simon.j.wright@mac.com>
Newsgroups: comp.lang.ada
Subject: Re: Containers - nontrivial element access
Date: Wed, 03 Oct 2007 20:15:42 +0100
Organization: Pushface
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Date: 2007-10-03T20:15:42+01:00
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"Jeffrey R. Carter" <spam.jrcarter.not@acm.nospam.org> writes:

> C++ uses reference semantics, so that a modification of a field
> modifies the value in the data structure. Ada uses value semantics,
> so that modification of a field does not modify the value in the
> data structure.

I'm no expert, but I would have expected C++ to distinguish given

   struct Foo {
      ...
   };

the three different functions

   Foo return_by_value();
   Foo* return_by_access();
   Foo& return_by_reference();

I wonder what the difference between Foo* and Foo& is? I don't suppose
there's any difference at the object code level? (except Foo* can be
0).

--S