pub const EMPTY_VTABLE: NrosRmwVtable;Expand description
A vtable with every slot NULL — the base for struct-update syntax.
Phase 376 W4 — a vtable literal must name EVERY field, and this crate’s
tests build 26 of them. Adding a slot therefore meant adding one None,
line to each, twenty-six times: tedious, and a place to miss one. The
compiler catches a miss, but only after the diff has grown by the slot count
times twenty-six. With this, a test names the slots it actually scripts and
ends with ..EMPTY_VTABLE, so a new slot costs one line in the header and
nothing here.
Deliberately a const and not a Default impl: Default would make an
all-NULL vtable constructible by accident, and an all-NULL vtable is exactly
what nros_rmw_cffi_register must REFUSE (issue 0349). A const used
explicitly as a literal’s base cannot be reached that way.