Trait rustc_middle::ty::fold::TypeFolder

pub trait TypeFolder<'tcx>: Sized {
    fn tcx<'a>(&'a self) -> TyCtxt<'tcx>;

    fn fold_binder<T>(&mut self, t: Binder<'tcx, T>) -> Binder<'tcx, T>
    where
        T: TypeFoldable<'tcx>,
    { ... }
    fn fold_ty(&mut self, t: Ty<'tcx>) -> Ty<'tcx> { ... }
    fn fold_region(&mut self, r: Region<'tcx>) -> Region<'tcx> { ... }
    fn fold_const(&mut self, c: &'tcx Const<'tcx>) -> &'tcx Const<'tcx> { ... }
    fn fold_mir_const(&mut self, c: ConstantKind<'tcx>) -> ConstantKind<'tcx> { ... }
}

The TypeFolder trait defines the actual folding. There is a method defined for every foldable type. Each of these has a default implementation that does an “identity” fold. Within each identity fold, it should invoke foo.fold_with(self) to fold each sub-item.

Required methods

fn tcx<'a>(&'a self) -> TyCtxt<'tcx>

Provided methods

fn fold_binder<T>(&mut self, t: Binder<'tcx, T>) -> Binder<'tcx, T> where
    T: TypeFoldable<'tcx>, 

fn fold_ty(&mut self, t: Ty<'tcx>) -> Ty<'tcx>

fn fold_region(&mut self, r: Region<'tcx>) -> Region<'tcx>

fn fold_const(&mut self, c: &'tcx Const<'tcx>) -> &'tcx Const<'tcx>

fn fold_mir_const(&mut self, c: ConstantKind<'tcx>) -> ConstantKind<'tcx>

Implementors

impl<'a, 'tcx> TypeFolder<'tcx> for rustc_middle::ty::print::pretty::RegionFolder<'a, 'tcx>

impl<'a, 'tcx> TypeFolder<'tcx> for SubstFolder<'a, 'tcx>

impl<'a, 'tcx> TypeFolder<'tcx> for BoundVarReplacer<'a, 'tcx>

impl<'a, 'tcx> TypeFolder<'tcx> for rustc_middle::ty::fold::RegionFolder<'a, 'tcx>

impl<'tcx> TypeFolder<'tcx> for RegionEraserVisitor<'tcx>

impl<'tcx> TypeFolder<'tcx> for NormalizeAfterErasingRegionsFolder<'tcx>

impl<'tcx> TypeFolder<'tcx> for OpaqueTypeExpander<'tcx>

impl<'tcx> TypeFolder<'tcx> for Shifter<'tcx>

impl<'tcx, F, G, H> TypeFolder<'tcx> for BottomUpFolder<'tcx, F, G, H> where
    F: FnMut(Ty<'tcx>) -> Ty<'tcx>,
    G: FnMut(Region<'tcx>) -> Region<'tcx>,
    H: FnMut(&'tcx Const<'tcx>) -> &'tcx Const<'tcx>,