pub type NonZeroU16 = NonZero<u16>;
Expand description
An integer that is known not to equal zero.
This enables some memory layout optimization.
For example, Option<NonZeroU16>
is the same size as u16
:
use std::mem::size_of;
assert_eq!(size_of::<Option<core::num::NonZeroU16>>(), size_of::<u16>());
§Layout
NonZeroU16
is guaranteed to have the same layout and bit validity as u16
with the exception that 0
is not a valid instance.
Option<NonZeroU16>
is guaranteed to be compatible with u16
,
including in FFI.
Thanks to the null pointer optimization,
NonZeroU16
and Option<NonZeroU16>
are guaranteed to have the same size and alignment:
use std::num::NonZeroU16;
assert_eq!(size_of::<NonZeroU16>(), size_of::<Option<NonZeroU16>>());
assert_eq!(align_of::<NonZeroU16>(), align_of::<Option<NonZeroU16>>());
Aliased Type§
struct NonZeroU16(/* private fields */);