Re: Using a generic instance to implement a public subprogram?

[Gautier <gautier@fakeaddress.nil>]

Peter C. Chapin:

...
> GNAT says this:
> 
> check.adb:3:14: missing body for "Sqrt" declared at check.ads:5
> check.adb:21:13: "Sqrt" conflicts with declaration at check.ads:5
> check.adb:21:13: instantiation cannot provide body for it
> 
> The first message I understand. The last two I'm not clear about. Is 
> GNAT telling me that my declarations conflict in some way and because of 
> that it can't do the instantiation, or is the instantiation the *cause* 
> of the conflict? Is it possible to do what I'm trying to do here?

No idea whether GNAT is right or not, but the following works (I came across the 
same problem at least one time...):

    function Sqrt_internal is
       new Unary_Operation(Operation => Elementary_Functions.Sqrt);

    function Sqrt(V : Vector) return Vector
       renames Sqrt_internal;

Note that the compilation of your code with ObjectAda 7.2.2 fails too; it says 
the following:
"
check.adb: Error: line 21 col 13 LRM:8.3(26), Illegal to override declaration in 
same region, Introducing new declaration anyway

check.adb: Error: line 27 col 1 LRM:3.11.1(6), Completion required for 
specification 'Sqrt', Continuing

Front end of ..\..\check.adb failed with 2 errors.
"
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Gautier         -- http://www.mysunrise.ch/users/gdm/index.htm
Ada programming -- http://www.mysunrise.ch/users/gdm/gsoft.htm

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