Const equivalents of raw pointer and NonNull methods.
NonNull
These functions were removed in 0.3.0 because there is an equivalent const fn in the standard library:
deref: raw pointers can be dereferenced since Rust 1.58.0
deref
deref_mut: Rust 1.83.0 allows dereferencing mutable pointers.
deref_mut
<*const>::as_ref
<*const T>::is_null