This is a reply to the first comment on my StackOverflow answer here: http://stackoverflow.com/a/37444724/2397809

explanation.md

The interface and behavior for the following traits and metafunctions (as they currently stand on the CallableTraits develop branch) are unlikely to change, for the most part. I explain what I mean by "for the most part" after this list:

• add_member_const
• add_member_volatile
• add_member_cv
• add_member_lvalue_reference
• add_member_rvalue_reference
• add_varargs
• remove_member_const
• remove_member_cv
• remove_member_reference
• remove_member_volatile
• remove_varargs
• is_const_member
• is_cv_member
• is_volatile_member
• is_lvalue_reference_member
• is_rvalue_reference_member
• is_reference_member
• has_varargs
• has_void_return
• has_member_qualifiers
• remove_member_pointer
• apply_member_pointer
• arg_at
• args
• expand_args
• function_type

All other library features in CallableTraits are either back on the drawing board, or on the chopping block. Although I'm still working to achieve 100% coverage, most (if not all) of the features listed above are thoroughly tested. Although relatively stable, some things may change as the library approaches version 1.0:

1. The library may adopt a <type_traits>-style interface, where the following assert will not fail:

   static_assert(std::is_same<typename add_member_const::type, add_member_const_t>::value, "");

I haven't decided whether to do this yet -- I would like to receive feedback first. The <type_traits> approach is more friendly to higher-order metafunctions and lazy template instantiations. It's also simply more conventional.

2. Invalid template parameters may be handled differently.

3. Currently, the features above do not account for C++17 transaction_safe or C++17 noexcept. These will be handled before 1.0 is released.

I hope this answers your question.