Re: guile macros and binary API

> As a background, Fortran allows you to declare "foreign" functions, for example,
> like this:
>
> type, public, bind(c) :: scm_t
>    private
>    integer(c_intptr_t) :: do_not_ever_use
> end type scm_t
>
> interface
>   function scm_symbol_p (obj) result (yes) bind (c)
>      type(scm_t), intent(in), value :: obj
>     type(scm_t) :: yes
>   end function scm_symbol_p
>   ...
> end interface