Struct rustc_metadata::rmeta::LazyValue
source · struct LazyValue<T> {
position: NonZeroUsize,
_marker: PhantomData<fn() -> T>,
}
Expand description
A value of type T referred to by its absolute position in the metadata, and which can be decoded lazily.
Metadata is effective a tree, encoded in post-order,
and with the root’s position written next to the header.
That means every single LazyValue
points to some previous
location in the metadata and is part of a larger node.
The first LazyValue
in a node is encoded as the backwards
distance from the position where the containing node
starts and where the LazyValue
points to, while the rest
use the forward distance from the previous LazyValue
.
Distances start at 1, as 0-byte nodes are invalid.
Also invalid are nodes being referred in a different
order than they were encoded in.
Fields§
§position: NonZeroUsize
§_marker: PhantomData<fn() -> T>
Implementations§
source§impl<T: ParameterizedOverTcx> LazyValue<T>
impl<T: ParameterizedOverTcx> LazyValue<T>
source§impl<T> LazyValue<T>
impl<T> LazyValue<T>
fn from_position(position: NonZeroUsize) -> LazyValue<T>
Trait Implementations§
source§impl<'a, 'tcx, T> Decodable<DecodeContext<'a, 'tcx>> for LazyValue<T>
impl<'a, 'tcx, T> Decodable<DecodeContext<'a, 'tcx>> for LazyValue<T>
fn decode(decoder: &mut DecodeContext<'a, 'tcx>) -> Self
source§impl<'a, 'tcx, T> Encodable<EncodeContext<'a, 'tcx>> for LazyValue<T>
impl<'a, 'tcx, T> Encodable<EncodeContext<'a, 'tcx>> for LazyValue<T>
fn encode(&self, e: &mut EncodeContext<'a, 'tcx>)
source§impl<T: ParameterizedOverTcx> ParameterizedOverTcx for LazyValue<T>
impl<T: ParameterizedOverTcx> ParameterizedOverTcx for LazyValue<T>
type Value<'tcx> = LazyValue<<T as ParameterizedOverTcx>::Value<'tcx>>
impl<T> Copy for LazyValue<T>
Auto Trait Implementations§
impl<T> RefUnwindSafe for LazyValue<T>
impl<T> Send for LazyValue<T>
impl<T> Sync for LazyValue<T>
impl<T> Unpin for LazyValue<T>
impl<T> UnwindSafe for LazyValue<T>
Blanket Implementations§
source§impl<T> BorrowMut<T> for Twhere
T: ?Sized,
impl<T> BorrowMut<T> for Twhere T: ?Sized,
source§fn borrow_mut(&mut self) -> &mut T
fn borrow_mut(&mut self) -> &mut T
Layout§
Note: Most layout information is completely unstable and may even differ between compilations. The only exception is types with certain repr(...)
attributes. Please see the Rust Reference's “Type Layout” chapter for details on type layout guarantees.
Size: 8 bytes