#include <stdio.h>

void f0(int) { puts("f0"); }
void f1(const int&) { puts("f1"); }

template <typename T> void Fun(void (*f)(T)) { f(0); }

int main()
{
  Fun(f0);      // this works of course.
  Fun(f1);      // should this work?
  return 0;
}

My compiler barfs at Fun(f1) complaining about passing `void (*)(const
int&)' to 'void (*)(int)'. I thought T should be `const int&' in the
second case. My current work around is to provide overloaded Funs. I
browsed the dec96pub wp and still feel fuzzy about this. Could some std
guy/langlawyer clarify this for me. Thanks in advance.

Fly.


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fleye@my-deja.com wrote:

> #include <stdio.h>
>
> void f0(int) { puts("f0"); }
> void f1(const int&) { puts("f1"); }
>
> template <typename T> void Fun(void (*f)(T)) { f(0); }
>
> int main()
> {
>   Fun(f0);      // this works of course.
>   Fun(f1);      // should this work?
>   return 0;
> }
>
> My compiler barfs at Fun(f1) complaining about passing `void (*)(const
> int&)' to 'void (*)(int)'. I thought T should be `const int&' in the
> second case. My current work around is to provide overloaded Funs. I
> browsed the dec96pub wp and still feel fuzzy about this. Could some std
> guy/langlawyer clarify this for me. Thanks in advance.

I read the section on template argument deduction. It seems that both cases
should work.

Then I tried it with my favorite compiler. It worked fine.

    -- Darin


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