Re: [Boost-users] [fusion?] [Phoenix?] Calling arbitrary method with collection of args

Subject: Re: [Boost-users] [fusion?] [Phoenix?] Calling arbitrary method with collection of args
From: Nat Goodspeed (nat_at_[hidden])
Date: 2010-03-19 11:25:08

Kim Kuen Tang wrote:

>  From my opinion i 'll say that there is no ready-to-use function in boost.

Hmm! Further digging turned up boost::fusion::invoke(). The following 
short program builds and runs as expected using Boost 1.39.0 with gcc 4.0.1.

The Fusion documentation says that support for boost::array is entirely 
implemented with the non-intrusive Fusion extension mechanism. Hopefully 
it won't be too hard to adapt the boost::array extension for our own 
container. (I'm a bit surprised not to find existing support for 
std::vector; presumably that's been done a few times by individuals.)

#include <iostream>
#include <boost/array.hpp>
#include <boost/fusion/include/array.hpp>
#include <boost/fusion/functional/invocation/invoke.hpp>

int somefunc(const std::string& a, const std::string& b)
{
     std::cout << "somefunc('" << a << "', '" << b << "')\n";
     return 17;
}

int main(int argc, char *argv[])
{
     boost::array<std::string, 2> args = {{"first", "second"}};
     int result = boost::fusion::invoke(somefunc, args);
     std::cout << "somefunc() returned " << result << '\n';
     return 0;
}