Struct RegionFolder

pub struct RegionFolder<'a, I: Interner> {
    cx: I,
    current_index: DebruijnIndex,
    fold_region_fn: &'a mut (dyn FnMut(I::Region, DebruijnIndex) -> I::Region + 'a),
}

Folds over the substructure of a type, visiting its component types and all regions that occur free within it.

That is, function pointer types and trait object can introduce new bound regions which are not visited by this visitors as they are not free; only regions that occur free will be visited by fld_r.

Fields

cx: I

current_index: DebruijnIndex

Stores the index of a binder just outside the stuff we have visited. So this begins as INNERMOST; when we pass through a binder, it is incremented (via shift_in).

fold_region_fn: &'a mut (dyn FnMut(I::Region, DebruijnIndex) -> I::Region + 'a)

Callback invokes for each free region. The DebruijnIndex points to the binder just outside the ones we have passed through.

Implementations

impl<'a, I: Interner> RegionFolder<'a, I>

pub fn new( cx: I, fold_region_fn: &'a mut dyn FnMut(I::Region, DebruijnIndex) -> I::Region, ) -> RegionFolder<'a, I>

Trait Implementations

impl<'a, I: Interner> TypeFolder<I> for RegionFolder<'a, I>

fn cx(&self) -> I

fn fold_binder<T: TypeFoldable<I>>(&mut self, t: Binder<I, T>) -> Binder<I, T>

fn fold_region(&mut self, r: I::Region) -> I::Region

fn fold_ty(&mut self, t: I::Ty) -> I::Ty

fn fold_const(&mut self, c: I::Const) -> I::Const

fn fold_predicate(&mut self, p: I::Predicate) -> I::Predicate

Layout

Note: Unable to compute type layout, possibly due to this type having generic parameters. Layout can only be computed for concrete, fully-instantiated types.