Exercise 6-0

Find the smallest type in a sequence with boost::mpl::copy. More...

Files
file	exercise-6-0.hpp
	Solution to Exercise 6-0.

Namespaces
namespace	anonymous_namespace{chapter-6.cpp}::test_6_0
	Tests functionality from Exercise 6-0.
namespace	exercise_6_0
	Encapsulate solution for Exercise 6-0.

Detailed Description

Find the smallest type in a sequence with boost::mpl::copy.

6-0. Use mpl::copy with a hand-built inserter to write a smallest
     metafunction that finds the smallest of a sequence of types.  That is:

BOOST_STATIC_ASSERT((
    boost::is_same<
        smallest< mpl::vector<int[2], char, double&> >::type,
        char
    >::value
));

Now that you've done it, is it a good way to solve that problem?  Why or why
not?

"Is it a good way to solve the problem?" It's not too bad; perhaps boost::mpl::accumulate would be better as it eliminates the need for the inserter, thus removing a pretty boring pass-through type (replace_with_smaller), and removing the confusing name, "copy", when we're really doing a iterative traversal and returning a single value.