Function mrb_define_module_function

pub unsafe extern "C" fn mrb_define_module_function(
    mrb: *mut mrb_state,
    cla: *mut RClass,
    name: *const c_char,
    fun: mrb_func_t,
    aspec: mrb_aspec,
)

Defines a module function.

Example:

   module Foo
     def Foo.bar
     end
   end
   // C style
   mrb_value bar_method(mrb_state* mrb, mrb_value self){
     return mrb_nil_value();
   }
   void mrb_example_gem_init(mrb_state* mrb){
     struct RClass *foo;
     foo = mrb_define_module(mrb, "Foo");
     mrb_define_module_function(mrb, foo, "bar", bar_method, MRB_ARGS_NONE());
   }

@param mrb The MRuby state reference. @param cla The module where the module function will be defined. @param name The name of the module function being defined. @param fun The function pointer to the module function definition. @param aspec The method parameters declaration.