Function CSTL_u32string_move_assign

pub unsafe extern "C" fn CSTL_u32string_move_assign(
    instance: CSTL_UTF32StringRef,
    alloc: *mut CSTL_Alloc,
    other_instance: CSTL_UTF32StringRef,
    other_alloc: *mut CSTL_Alloc,
    propagate_alloc: bool,
)

Moves the contents of other_instance to the contents of instance.

If propagate_alloc == true storage is replaced with storage of other_instance. Then, instance uses other_alloc as its allocator.

If propagate_alloc == false && alloc != other_alloc then storage is reused and individual characters of other are moved in. Then, instance uses alloc as its allocator.

You are responsible for replacing the allocator outside of CSTL_UTF32StringVal if applicable.