Struct rustc_infer::infer::at::At

pub struct At<'a, 'tcx> {
    pub infcx: &'a InferCtxt<'a, 'tcx>,
    pub cause: &'a ObligationCause<'tcx>,
    pub param_env: ParamEnv<'tcx>,
}

Fields

infcx: &'a InferCtxt<'a, 'tcx>

cause: &'a ObligationCause<'tcx>

param_env: ParamEnv<'tcx>

Implementations

impl<'a, 'tcx> At<'a, 'tcx>

pub fn eq_impl_headers(
    self,
    expected: &ImplHeader<'tcx>,
    actual: &ImplHeader<'tcx>
) -> InferResult<'tcx, ()>

Hacky routine for equating two impl headers in coherence.

pub fn sub_exp<T>(
    self,
    a_is_expected: bool,
    a: T,
    b: T
) -> InferResult<'tcx, ()> where
    T: ToTrace<'tcx>, 

Makes a <: b, where a may or may not be expected.

pub fn sup<T>(self, expected: T, actual: T) -> InferResult<'tcx, ()> where
    T: ToTrace<'tcx>, 

Makes actual <: expected. For example, if type-checking a call like foo(x), where foo: fn(i32), you might have sup(i32, x), since the “expected” type is the type that appears in the signature.

pub fn sub<T>(self, expected: T, actual: T) -> InferResult<'tcx, ()> where
    T: ToTrace<'tcx>, 

Makes expected <: actual.

pub fn eq_exp<T>(self, a_is_expected: bool, a: T, b: T) -> InferResult<'tcx, ()> where
    T: ToTrace<'tcx>, 

Makes expected <: actual.

pub fn eq<T>(self, expected: T, actual: T) -> InferResult<'tcx, ()> where
    T: ToTrace<'tcx>, 

Makes expected <: actual.

pub fn relate<T>(
    self,
    expected: T,
    variance: Variance,
    actual: T
) -> InferResult<'tcx, ()> where
    T: ToTrace<'tcx>, 

pub fn lub<T>(self, expected: T, actual: T) -> InferResult<'tcx, T> where
    T: ToTrace<'tcx>, 

Computes the least-upper-bound, or mutual supertype, of two values. The order of the arguments doesn’t matter, but since this can result in an error (e.g., if asked to compute LUB of u32 and i32), it is meaningful to call one of them the “expected type”.

pub fn glb<T>(self, expected: T, actual: T) -> InferResult<'tcx, T> where
    T: ToTrace<'tcx>, 

Computes the greatest-lower-bound, or mutual subtype, of two values. As with lub order doesn’t matter, except for error cases.

pub fn trace<T>(self, expected: T, actual: T) -> Trace<'a, 'tcx> where
    T: ToTrace<'tcx>, 

Sets the “trace” values that will be used for error-reporting, but doesn’t actually perform any operation yet (this is useful when you want to set the trace using distinct values from those you wish to operate upon).

pub fn trace_exp<T>(self, a_is_expected: bool, a: T, b: T) -> Trace<'a, 'tcx> where
    T: ToTrace<'tcx>, 

Like trace, but the expected value is determined by the boolean argument (if true, then the first argument a is the “expected” value).