Is a template declaration such as below valid? (My compiler doesn't support it,
and I couldn't find anything explicit in the April 95 draft)

    template<class T, T value>   // The second param. depends on the first one
    class Named {
        operator T& const () const { return value; }
    };

If it is,
    Named<String, "Trans aequora abiit Chloe"> Blah;
could be used instead of
    #define Blah String("Trans aequora abiit Chloe")

The first version obeys scope rules, while the #define version doesn't.


denis (denis.bider@abm.si)
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>>>>> "B" == biderd  <biderd@abm.si> writes:
[...]
B>     template<class T, T value>   // The second param.
                                    // depends on the first one
B>     class Named {
B>         operator T& const () const { return value; }
B>     };

I believe it is OK (I vaguely remember a similar example in the DWP),
but I'm not positive. If it is, it certainly constrains the T types
for which you can instantiate this.

B> If it is,
B>     Named<String, "Trans aequora abiit Chloe"> Blah;
B> could be used instead of
B>     #define Blah String("Trans aequora abiit Chloe")

Surely not. "Trans aequora abiit Chloe" is of type char const*
(since Stockholm, previously char*), not String. Remember that
template instantiation is a compile-time thing --- it's not
reasonable to expect compile-time invocation of user- or
library-defined conversions.

 Daveed
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