🚀 go-pugleaf

tony@online.tmx.com.au (Tony Cook) writes:

>Steve Clamage (clamage@Eng) wrote:

>: In the mean time, you could write a specialization of Foo<X>::compare
>: that throws an exception or invokes "assert(0)" to allow your code
>: to compile and link. That is, for example, if you use Foo<complex>,
>: you could provide the specialization
>: 	int Foo<complex>::compare(const complex&) { assert(0); return 0; }
>: which will prevent the compiler from generating a version from the template,
>: and will thus allow your program to compile and link.

>Can we instead _declare_ the specialization and not define it:

>    extern int Foo<complex>::compare(const complex &);

>So that we see an error at link time rather than run-time?

No. The declaration does not prevent instantiation if any use is made
of the function. That is, the declaration tells the compiler that
particular compare function is supposed to exist. If it is needed
but not found at link time, the system will generate it from the
template definition.

--
Steve Clamage, stephen.clamage@eng.sun.com

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