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Hi All,

how can i enforce the requirement below ?

template<class RANDOM>//template member function
double A<RANDOM>:perator()(RANDOM& u){
/* requirement: RANDOM::result_type is double */

/* body of the function */
};

* er:
>
> how can i enforce the requirement below ?
>
> template<class RANDOM>//template member function
> double A<RANDOM>:perator()(RANDOM& u){
> /* requirement: RANDOM::result_type is double */
>
> /* body of the function */
> };

The Boost library provides facilities for compile time assertions and
compile time checking of whether two types are the same. Compile time
assertions will become part of the language in C++0x, but with slightly
different syntax than the Boost macro. There is however a good chance
that it would be better to rethink the design rather than enforce.

Btw., don't use all uppercase for non-macro names.

Reserve all uppercase for macro names, to reduce possibility of name
collisions.


Cheers, & hth.,

- Alf


--
A: Because it messes up the order in which people normally read text.
Q: Why is it such a bad thing?
A: Top-posting.
Q: What is the most annoying thing on usenet and in e-mail?

On Jan 29, 10:12 pm, "Alf P. Steinbach" <al...@start.no> wrote:
> * er:
>
>
>
> > how can i enforce the requirement below ?
>
> > template<class RANDOM>//template member function
> > double A<RANDOM>:perator()(RANDOM& u){
> > /* requirement: RANDOM::result_type is double */
>
> > /* body of the function */
> > };
>
> The Boost library provides facilities for compile time assertions and
> compile time checking of whether two types are the same. Compile time

Do you mean BOOST_STATIC_ASSERT? If so, specifically how do I define
the predicate in my case?

> assertions will become part of the language in C++0x, but with slightly
> different syntax than the Boost macro. There is however a good chance
> that it would be better to rethink the design rather than enforce.

Basically in my example A<Random>:perator()(Random&) returns a
random value derived from Random(), that's all. Any suggestion on how
to rethink the design then?


>
> Btw., don't use all uppercase for non-macro names.

OK

>
> Reserve all uppercase for macro names, to reduce possibility of name
> collisions.
>
> Cheers, & hth.,

Thanks.

>
> - Alf
>
> --
> A: Because it messes up the order in which people normally read text.
> Q: Why is it such a bad thing?
> A: Top-posting.
> Q: What is the most annoying thing on usenet and in e-mail?