fn unify_trait<'tcx>(
lhs: TraitRef<'tcx>,
rhs: TraitRef<'tcx>,
identity: &[GenericArg<'tcx>],
infcx: &InferCtxt<'tcx>,
cause: &ObligationCause<'tcx>,
param_env: ParamEnv<'tcx>,
tcx: TyCtxt<'tcx>,
) -> Option<Mono<'tcx>>
Expand description
only handle the case that rhs does not have any infer types
e.g., <T as Into<U>> == <Foo as Into<Bar>> => Some(T=Foo, U=Bar))