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From: "Alejandro R. Mosteo" <alejandro@mosteo.com>
Newsgroups: comp.lang.ada
Subject: Re: Generic formal type with 'Image
Date: Wed, 6 Jun 2018 20:35:51 +0200
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Xref: reader02.eternal-september.org comp.lang.ada:52960
Date: 2018-06-06T20:35:51+02:00
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Thanks for the suggestions, and the link to the AI. I find these 
discussions fascinating.

Alex.

On 06/06/2018 15:03, Alejandro R. Mosteo wrote:
> I'm pretty sure the answer is "no", but just in case:
> 
> Is there a formal for a generic that serves for any type that has a 
> predefined 'Image?
> 
> The purpose is to avoid:
> 
> generic
>     type Printable is ... -- What should go here?
>     with function Image (P : Printable) return String is <>;
> package
> 
> and then have to pass the 'Image attribute as the Image function in all 
> instantiations.
> 
> The closest thing I can think of is (<>) but that won't do for floating 
> point types.
> 
> I understand this is an unusually narrow case (I need a generic for many 
> numeric types, both discrete and floating, and this would save me some 
> typing -- that I have already spent here anyway.)
> 
> With these issues I feel a kind of overlap/missed connection between 
> attributes and interfaces.
> 
> Thanks,
> Alex.