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From: Niklas Holsti <niklas.holsti@tidorum.invalid>
Newsgroups: comp.lang.ada
Subject: Re: How to access an array using two different indexing schemes
Date: Thu, 30 Nov 2017 16:47:36 +0200
Organization: Tidorum Ltd
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Xref: reader02.eternal-september.org comp.lang.ada:49275
Date: 2017-11-30T16:47:36+02:00
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On 17-11-30 13:40 , AdaMagica wrote:
> OK, I dived into the RM:
>
> 8.5.1(4) The renamed entity shall be an object.
> 3.3(12) [An object is a] view conversion of another object.
> 4.6(5/2) A type_conversion whose operand is the name of an
> object is called a view conversion if both its target type
> and operand type are tagged, or if it appears in a call as
> an actual parameter of mode out or in out; other
> type_conversions are called value conversions.
>
> So my conclusion is:
>
> The renamings here are illegal (not tagged).
> The subprogram calls as shown in my previous post are legal.
>
> Didn't try however. Good luck for you!

Perhaps the next Ada revision could extend 4.6(5/2) to include a type 
conversion in a renaming, as a view conversion?

It seems to me that on the implementation level, this case (declaring a 
new local variable to be a renaming of a type conversion of an object) 
should be very similar to the actual-parameter case of 4.6(5/2).

-- 
Niklas Holsti
Tidorum Ltd
niklas holsti tidorum fi
       .      @       .