Re: [boost] BOOST_STATIC_CONSTANT problems on Borland

From: Terje Slettebø (tslettebo_at_[hidden])
Date: 2003-01-01 19:08:34

>From: "Jaap Suter" <J.Suter_at_[hidden]>

> Compiling the following code on Borland 5.6:
> _________________________________
>
> template < size_t N > struct widget {};
>
> template < class T >
> struct foo
> {
>     BOOST_STATIC_CONSTANT( size_t, static_constant = 42 );
>     typedef widget< static_constant > bar_1;
>     size_t bar_2() { return static_constant; }
> };
> _________________________________
>
> Gives the following three errors on the line that defines bar_1:
>
> Member foo<T>::static_constant cannot be used without an object
> Invalid template argument list
> Declaration terminated incorrectly
>
> The bar_2 member function compiles fine.
> Also, if I make foo a non-template class, everything compiles fine.
>
> This compiler does not result in the definition of
> BOOST_NO_INCLASS_MEMBER_INITIALIZATION so the enum-hack isn't used.
However,
> if I do in fact use the enum-hack the above code compiles fine too.
>
> Am I missing something here, or maybe Borlands static-class-constants
> behaviour is not 100% perfect....

You could say that... :) (the latter) Try fully qualifying the constant
name, as recommended here
(http://www.boost.org/more/int_const_guidelines.htm):

typedef widget< ::foo<T>::static_constant > bar_1;

I recommend that you use BOOST_STATIC_CONSTANT, as above (and not enum), as
enum doesn't always work well on this compiler (which is why static const is
used for it by this macro).

Regards,

Terje