Re: [Boost-users] Array of types to change template function in a for loop

Subject: Re: [Boost-users] Array of types to change template function in a for loop
From: Steven Watanabe (watanabesj_at_[hidden])
Date: 2008-09-12 11:46:27

AMDG

Patrick Loney wrote:
> I've got some code which needs to call a template function on different
> objects (potentially in a for loop). I'm currently doing this using an
> array of function ptrs but like the idea of an array of types. 
> <snip>
>
> I believe this should be possible using the pre-processor or meta
> programming parts of boost but have no experience of either and was
> hoping for some pointers. Is it possible and is it, IYO, better than the
> function pointer method I'm currently using?
>   

boost::mpl::for_each does what you want
http://www.boost.org/doc/libs/1_36_0/libs/mpl/doc/refmanual/for-each.html
(untested):

template<class T>
struct wrap {};

struct func_f {
    typedef void result_type;
    template<class T>
    void operator()(const wrap<T>&, const std:;string& s) const {
        func<T>(s);
    }
};

int main() {
    boost::mpl::for_each<boost::mpl::vector<Obj1, Obj2, Obj3>,
            wrap<boost::mpl::_1> >(
                boost::bind(func_f(), _1, "testid"));
}

In Christ,
Steven Watanabe