Lines Matching defs:Option
99 // `Option<&T>` and `Option<Box<T>>` are guaranteed to represent `None` as null.
103 // `Option<&mut T>` never implements `Clone`, so there's no need for an impl of
106 unsafe impl<T: ?Sized> IsZero for Option<&T> {
113 unsafe impl<T: ?Sized> IsZero for Option<Box<T>> {
120 // `Option<num::NonZeroU32>` and similar have a representation guarantee that
122 // that transmuting between `NonZeroU32` and `Option<num::NonZeroU32>` works.
129 unsafe impl IsZero for Option<core::num::$t> {
155 unsafe impl IsZero for Option<$t> {
200 Option<bool>,
201 Option<Option<bool>>,
202 Option<Option<Option<bool>>>,