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[@ 2012-07-26 14:30 UTC (permalink / raw)]

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From: "Randy Brukardt" <randy@rrsoftware.com>
Newsgroups: comp.lang.ada
Subject: Re: Signature Package With Generic Proceedure
Date: Mon, 23 Jul 2012 21:53:20 -0500
Organization: Jacob Sparre Andersen Research & Innovation
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"Keean Schupke" <keean.schupke@googlemail.com> wrote in message 
news:79925d0c-b2dd-44a3-9451-48f0ee19485f@googlegroups.com...
...
> This is datatype generic programming, one of the things I thought Ada is 
> good at.
> Signatures are the only way in Ada of doing this with no runtime cost, and 
> the only way
> using generics. Signatures belong to a family of constructs across several 
> languages with
> similar properties. For example:

There's nothing in Ada that says generics have to be implemented with "no 
runtime cost". Many Ada 83 implementations, and a few more recent 
implementations, share all generic instantiations. The effect is very 
similar to tagged type dispatching, and it's most useful when there are a 
lot of instances in a program. Janus/Ada certainly does this (it might be 
the last to do "universal generic sharing"). Some Ada implementations do 
"partial generic sharing", where the parameters involved determine if 
sharing is used.

Normally, at this point, I'd say something about premature optimization, but 
I realize from your past messages that you're already beyond that stage, so 
I won't say any more.

                                       Randy.