Re: Unchecked_Deallocation vs. delete

[Robert A Duff <bobduff@shell01.TheWorld.com>]

Maciej Sobczak <see.my.homepage@gmail.com> writes:

> What's the benefit of Unchecked_Deallocation as a generic library
> procedure vs. built-in deallocation operator like delete in C++?
>
> The disadvantage, as far as I perceive it, is that it breaks the
> symmetry that should be expected with regard to the allocation
> operation. If "new" is built-in, then the deallocation should be built-
> in as well. Making it a generic library procedure just makes more work
> for the programmers for no clear reason.
>
> What clear reason am I missing?

I think you're right.  Not missing anything.

The original reason why U_D is a generic procedure is probably because
the designers of Ada 83 imagined that garbage collection would be
ubiquitous, so U_D would rarely be necesary.  I suppose they thought
that "with U_D;" would be a red flag, at the top of the package that
does such "evil" things.  Note that U_D is banished to chapter 13,
where all the other machine-dependent stuff lives.

- Bob