Re: knotty generics problem

Re: knotty generics problem

[mcsun!sun4nl!gufalet.let.rug.nl!rug4!laverman]

Andrew Dunstan wrote:
> Here is a fragment of abstracted Pascal code:
> 
>    procedure a(procedure b(procedure c));
>      procedure d;
>      .
>      .
>      b(d);
Nice ;-)

> I (and a number of people with better minds than mine!) have wracked
> my brains trying to think of a way to do this neatly in Ada. We have 
> all failed!
> I know it is provided for in 9X, but is there some genius out there
> who can suggest a way to do it with Ada as she is now?
You'ld have to use generics, as it is possible to use a procedure as
generic parameter. The syntax specifies that as generic formal parameter
a subprogram_specification can be given (section 12.1). Subprogram
specifications however do not include generic subprogram specifications...

So, one level of procedure parameter would work, two wouldn't. mark
one for Pascal here ;-)

> (This example might seem contrived, but I assure you it comes from
> a working Pascal program.)
Then you'll have to wait for Ada9x...

Greetings, Bert
-- 
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  Bert Laverman,  Dept. of Computing Science, Groningen University
  Friendly mail to: laverman@cs.rug.nl      The rest to: /dev/null