Enum rustc_middle::ty::fast_reject::TreatParams
source · [−]pub enum TreatParams {
AsPlaceholder,
AsInfer,
}
Expand description
Generic parameters are pretty much just bound variables, e.g.
the type of fn foo<'a, T>(x: &'a T) -> u32 { ... }
can be thought of as
for<'a, T> fn(&'a T) -> u32
.
Typecheck of foo
has to succeed for all possible generic arguments, so
during typeck, we have to treat its generic parameters as if they
were placeholders.
But when calling foo
we only have to provide a specific generic argument.
In that case the generic parameters are instantiated with inference variables.
As we use simplify_type
before that instantiation happens, we just treat
generic parameters as if they were inference variables in that case.
Variants
AsPlaceholder
Treat parameters as placeholders in the given environment.
Note that this also causes us to treat projections as if they were placeholders. This is only correct if the given projection cannot be normalized in the current context. Even if normalization fails, it may still succeed later if the projection contains any inference variables.
AsInfer
Trait Implementations
sourceimpl Clone for TreatParams
impl Clone for TreatParams
sourcefn clone(&self) -> TreatParams
fn clone(&self) -> TreatParams
1.0.0 · sourcefn clone_from(&mut self, source: &Self)
fn clone_from(&mut self, source: &Self)
source
. Read moresourceimpl Debug for TreatParams
impl Debug for TreatParams
sourceimpl PartialEq<TreatParams> for TreatParams
impl PartialEq<TreatParams> for TreatParams
sourcefn eq(&self, other: &TreatParams) -> bool
fn eq(&self, other: &TreatParams) -> bool
impl Copy for TreatParams
impl Eq for TreatParams
impl StructuralEq for TreatParams
impl StructuralPartialEq for TreatParams
Auto Trait Implementations
impl RefUnwindSafe for TreatParams
impl Send for TreatParams
impl Sync for TreatParams
impl Unpin for TreatParams
impl UnwindSafe for TreatParams
Blanket Implementations
sourceimpl<'tcx, T> ArenaAllocatable<'tcx, IsCopy> for Twhere
T: Copy,
impl<'tcx, T> ArenaAllocatable<'tcx, IsCopy> for Twhere
T: Copy,
fn allocate_on(self, arena: &'a Arena<'tcx>) -> &'a mut T
fn allocate_from_iter(
arena: &'a Arena<'tcx>,
iter: impl IntoIterator<Item = T>
) -> &'a mut [T]ⓘNotable traits for &[u8]impl Read for &[u8]impl Write for &mut [u8]
sourceimpl<T> BorrowMut<T> for Twhere
T: ?Sized,
impl<T> BorrowMut<T> for Twhere
T: ?Sized,
const: unstable · sourcefn borrow_mut(&mut self) -> &mut T
fn borrow_mut(&mut self) -> &mut T
sourceimpl<T, R> InternIteratorElement<T, R> for T
impl<T, R> InternIteratorElement<T, R> for T
type Output = R
fn intern_with<I, F>(iter: I, f: F) -> <T as InternIteratorElement<T, R>>::Outputwhere
I: Iterator<Item = T>,
F: FnOnce(&[T]) -> R,
sourceimpl<T> MaybeResult<T> for T
impl<T> MaybeResult<T> for T
sourceimpl<CTX, T> Value<CTX> for Twhere
CTX: DepContext,
impl<CTX, T> Value<CTX> for Twhere
CTX: DepContext,
default fn from_cycle_error(tcx: CTX) -> T
impl<'a, T> Captures<'a> for Twhere
T: ?Sized,
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: 1 byte
Size for each variant:
AsPlaceholder
: 0 bytesAsInfer
: 0 bytes