Function R_set_altraw_Elt_method

pub unsafe extern "C" fn R_set_altraw_Elt_method(
    cls: R_altrep_class_t,
    fun: R_altraw_Elt_method_t,
)

Sets the function pointer inside the ALTREP class object. Behaviour is undefined if cls is not a compact complex vector class. There is no facility for unregistering ALTREP classes, so once a function pointer is set from a package shared library, it must not be unloaded.