Description

When using mixins from dynamic libraries, use this macro in your headers to forward declare a class as a mixin. This may be included separately and doesn't need to be in the same header as the actual mixin class definition.

If the first parameter is empty, the macro is equivalent to BOOST_DECLARE_MIXIN

Example: 

// Assuming MY_LIB_API is a macro that expands accordingly to the
// export/import symbols for the compiler you're using.
BOOST_DECLARE_EXPORTED_MIXIN(MY_LIB_API, my_mixin_type);