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Auto and alias traits

This commit is contained in:
Michael Goulet 2023-01-17 20:16:30 +00:00
parent 3d87a8e848
commit 45aa5c0f90
4 changed files with 171 additions and 23 deletions

View file

@ -92,16 +92,26 @@ pub(super) trait GoalKind<'tcx>: TypeFoldable<'tcx> + Copy {
impl_def_id: DefId,
) -> QueryResult<'tcx>;
fn consider_builtin_sized_candidate(
ecx: &mut EvalCtxt<'_, 'tcx>,
goal: Goal<'tcx, Self>,
) -> QueryResult<'tcx>;
fn consider_assumption(
ecx: &mut EvalCtxt<'_, 'tcx>,
goal: Goal<'tcx, Self>,
assumption: ty::Predicate<'tcx>,
) -> QueryResult<'tcx>;
fn consider_auto_trait_candidate(
ecx: &mut EvalCtxt<'_, 'tcx>,
goal: Goal<'tcx, Self>,
) -> QueryResult<'tcx>;
fn consider_trait_alias_candidate(
ecx: &mut EvalCtxt<'_, 'tcx>,
goal: Goal<'tcx, Self>,
) -> QueryResult<'tcx>;
fn consider_builtin_sized_candidate(
ecx: &mut EvalCtxt<'_, 'tcx>,
goal: Goal<'tcx, Self>,
) -> QueryResult<'tcx>;
}
impl<'tcx> EvalCtxt<'_, 'tcx> {
pub(super) fn assemble_and_evaluate_candidates<G: GoalKind<'tcx>>(
@ -198,7 +208,11 @@ impl<'tcx> EvalCtxt<'_, 'tcx> {
) {
let lang_items = self.tcx().lang_items();
let trait_def_id = goal.predicate.trait_def_id(self.tcx());
let result = if lang_items.sized_trait() == Some(trait_def_id) {
let result = if self.tcx().trait_is_auto(trait_def_id) {
G::consider_auto_trait_candidate(self, goal)
} else if self.tcx().trait_is_alias(trait_def_id) {
G::consider_trait_alias_candidate(self, goal)
} else if lang_items.sized_trait() == Some(trait_def_id) {
G::consider_builtin_sized_candidate(self, goal)
} else {
Err(NoSolution)
@ -315,8 +329,7 @@ impl<'tcx> EvalCtxt<'_, 'tcx> {
for assumption in
elaborate_predicates(tcx, bounds.iter().map(|bound| bound.with_self_ty(tcx, self_ty)))
{
match G::consider_assumption(self, goal, assumption.predicate)
{
match G::consider_assumption(self, goal, assumption.predicate) {
Ok(result) => {
candidates.push(Candidate { source: CandidateSource::BuiltinImpl, result })
}