Re: [Boost-users] [boost.bind] How to retrieve the function type of a boost::bind result

26 Jan 2009

      AMDG

Olaf Krzikalla wrote:
...
The following snippet won't compile since the compiler can't deduce 
the template argument:
template<typename T>
void foo(boost::function<T> func) { /*...*/ }
void bar() {}
void baz()
{
  foo(boost::bind(&bar));                           // error
  foo<void()>(boost::bind(&bar));                   // OK
  foo(boost::function<void()>(boost::bind(&bar)));  // OK
}
So how do I get the first line of baz to work? That is, is there a 
generic way to compute the boost::function type from the bind result?
There is not because the boost::function type is not unique.

Consider:

struct F {
    typedef void result_type;
    template<class T>
    void operator()(const T&) const;
};

boost::bind(F(), _1);

In Christ,
Steven Watanabe