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From: Robert A Duff <bobduff@shell01.TheWorld.com>
Subject: Re: Array type conversion
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Date: 2002-10-18T14:59:22+00:00
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"Keith" <nono@joimail.net> writes:

> What is the implementation consequence of not following  Ada reference
> manual section 4.6 12/1 "The component subtypes shall statically match"?
...
> I know that if the component subtypes have to statically match in an array
> conversion then  there is no need to check for matching constraints at run
> time like Ada 83. Does this speed up execution?

Yeah, but I think the main reason was to catch bugs at compile time
rather than run time.  There are several similar cases in Ada 95,
where a run-time check in Ada 83 was changed to a static check in Ada
95.

There might have been some other issue related to passing type
conversions as 'out' parameters, especially when the type is limited,
so the conversion cannot be implemented by copying.  I'm not sure
about that, and I don't feel like thinking about it right now.  ;-)

- Bob