out_param.md

out_param

This small class template out_param can be used to indicate in the function's signature that a given reference parameter is an output parameter:

#include <ak_toolbox/out_param.hpp>
using namespace ak_toolkit::xplicit;

void assign(out_param<std::string&> s, // < output parameter
            std::string const& v)
{
    s.get() = v;
}

It does not do any processing. The only benefit of using it is that you cannot pass a reference/pointer to a function unless you explicitly wrap it:

std::string s;
assign(out(s), "text");

This forces the function callers to be explicit about passing output arguments to it.