Re: Do people who use Ada also use ocaml or F#?

["Yannick Duchêne (Hibou57)" <yannick_duchene@yahoo.fr>]

Le Sat, 30 Oct 2010 22:54:39 +0200, Dmitry A. Kazakov  
<mailbox@dmitry-kazakov.de> a écrit:
>> Why should generic
>> usage be provable before instantiation ?
>
> Because you want to be able to deliver generic components.
What would be your requirements to state you are able to deliver a library  
? (I mean a library, as a library, not linked to an application).

Aren't generics similar to libraries ?

If you are to deliver an application designed upon generics, then it can  
be proved or unproved with that design.
If you are to deliver a generic as standalone, then there are things you  
will never be able to prove, right, but just like you will not be able to  
prove anything for a standalone library you've delivered. I would expect  
the requirements for the library should include suitability for one or  
some usages, precisely and priorly defined. This requirement for a  
standalone library, could be “it must be able of this and that”. The  
requirement for a standalone generic, in a similar way, could be “it must  
be able of this and that with these or these instantiation parameters” :  
just add a requirement on parameters. Impossible to guarantee anything  
outside of any defined scope, for whatever design. With generic,  
instantiation parameters matters, so just add this to the requirements.

Let's formalize a bit the deal.

Two distinct views of a generic from a client's point of view :

    1) Instance of a generic in an application
    2) Generic as standalone (as a library)

Then for the requirements :

    1) If the generic appears in an application, then the checks
       and requirements for the whole application applies.
    2) If the generic is standalone, then the kind of requirements
       which come with any library applies, plus, the added
       requirement that these latter requirements are at least
       verified for one or some clearly specified instantiation
       parameters.

What about such a deal ?

-- 
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les chiens.