Re: [Boost-users] [boost::function] problem with void type as argument type

On Mon, 2007-03-26 at 21:39 +0200, Seweryn Habdank-Wojewódzki wrote:

Hi!

Douglas Gregor wrote:

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template < typename T, typename U > void test ( boost::function & f ); [snip] boost::function h = &f3; boost::function i = &f4;

The problem is that "int(void)" is just an alternative spelling for "int()", i.e., a function type for a function that takes no parameters but returns an "int". A function type int() cannot match a template parameter T(U), because there is nothing to match the "U".

Thanks for reply. However still I do not know how to proceed in that case, because functions can not be partially specialized. Is there any opportunity to prepare more less such a function which will automatically detects arguments of boost::function template?

You can write multiple overloads of your "test" function, each of which accepts boost::function instances with a different number of function arguments: template<typename R> void test (boost::function& f); template void test (boost::function& f); template void test (boost::function& f); template void test (boost::function& f); Tedious, unfortunately, but it works. Cheers, Doug