Re: [Boost-users] Boost.Function: How does the template param mechanism work?

Douglas Gregor writes:

On Jun 19, 2005, at 10:32 AM, Brian Braatz wrote:

...

My question is, given:

boost::function< int (char, long) > func(&f);

how is it possible to pass the (char,long)? (I tried to receive this in a template as a single template param, or as three , but neither worked)

int (char, long) is a function type, i.e., the type that the pointer type int (*)(char, long) points to. You can pull apart a point type using partial specialization:

template<typename> struct Honk;

template struct Honk { };

Honk h; // R = int, T1 = char, T2 = long

...

I have been studying the headers, but the indirection used (FTSE :)

http://www.ftse.com/ ??

...

) is making it hard for me to figure this one out.

I am supposed to be giving a talk that covers some of the implementation techniques used in Boost.Function at the C++ Connections conference in Vegas,... if you can wait that long :) -- Dave Abrahams Boost Consulting www.boost-consulting.com