Struct chalk_ir::DynTy

pub struct DynTy<I: Interner> {
    pub bounds: Binders<QuantifiedWhereClauses<I>>,
}

A "DynTy" could be either a dyn Trait or an (opaque) impl Trait. Both of them are conceptually very related to a "existential type" of the form exists<T> { T: Trait }. The DynTy type represents those bounds.

The "binder" here represents the unknown self type. So, a type like impl for<'a> Fn(&'a u32) would be represented with two-levels of binder, as "depicted" here:

exists<type> {
   vec![
       // A QuantifiedWhereClause:
       forall<region> { ^1: Fn(&^0 u32) }
   ]
}

The outer exists<type> binder indicates that there exists some type that meets the criteria within, but that type is not known. It is referenced within the type using ^1, indicating a bound type with debruijn index 1 (i.e., skipping through one level of binder).

Fields

bounds: Binders<QuantifiedWhereClauses<I>>

Trait Implementations

impl<I: Clone + Interner> Clone for DynTy<I>

fn clone(&self) -> DynTy<I>

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<I: Interner> Debug for DynTy<I>

fn fmt(&self, fmt: &mut Formatter) -> Result<(), Error>

Formats the value using the given formatter.

impl<I: Eq + Interner> Eq for DynTy<I>

impl<I: Interner, _TI> Fold<I, _TI> for DynTy<I> where
    _TI: TargetInterner<I>, 

type Result = DynTy<_TI>

The type of value that will be produced once folding is done. Typically this is Self, unless Self contains borrowed values, in which case owned values are produced (for example, one can fold over a &T value where T: Fold, in which case you get back a T, not a &T).

fn fold_with<'i>(
    &self,
    folder: &mut dyn Folder<'i, I, _TI>,
    outer_binder: DebruijnIndex
) -> Fallible<Self::Result> where
    I: 'i,
    _TI: 'i, 

Apply the given folder folder to self; binders is the number of binders that are in scope when beginning the folder. Typically binders starts as 0, but is adjusted when we encounter Binders<T> in the IR or other similar constructs.

impl<I: Interner> HasInterner for DynTy<I>

type Interner = I

impl<I: Hash + Interner> Hash for DynTy<I>

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given [Hasher].

fn hash_slice<H>(data: &[Self], state: &mut H) where
    H: Hasher, 

Feeds a slice of this type into the given [Hasher].

impl<I: PartialEq + Interner> PartialEq<DynTy<I>> for DynTy<I>

fn eq(&self, other: &DynTy<I>) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &DynTy<I>) -> bool

This method tests for !=.

impl<I: Interner> StructuralEq for DynTy<I>

impl<I: Interner> StructuralPartialEq for DynTy<I>

impl<I: Interner> Visit<I> for DynTy<I>

fn visit_with<'i, R: VisitResult>(
    &self,
    visitor: &mut dyn Visitor<'i, I, Result = R>,
    outer_binder: DebruijnIndex
) -> R where
    I: 'i, 

Apply the given visitor visitor to self; binders is the number of binders that are in scope when beginning the visitor. Typically binders starts as 0, but is adjusted when we encounter Binders<T> in the IR or other similar constructs.

impl<I: Interner> Zip<I> for DynTy<I>

fn zip_with<'i, Z: Zipper<'i, I>>(
    zipper: &mut Z,
    a: &Self,
    b: &Self
) -> Fallible<()> where
    I: 'i,