1 //! The type system. We currently use this to infer types for completion, hover
2 //! information and various assists.
7 macro_rules! eprintln {
8 ($($tt:tt)*) => { stdx::eprintln!($($tt)*) };
14 pub mod method_resolution;
37 cast::{CastTo, Caster},
39 interner::HasInterner,
43 expr::ExprId, type_ref::Rawness, ConstParamId, LifetimeParamId, TraitId, TypeAliasId,
47 use crate::{db::HirDatabase, display::HirDisplay, utils::generics};
49 pub use autoderef::autoderef;
50 pub use builder::TyBuilder;
52 pub use infer::{could_unify, InferenceResult};
54 associated_type_shorthand_candidates, callable_item_sig, CallableDefId, ImplTraitLoweringMode,
55 TyDefId, TyLoweringContext, ValueTyDefId,
57 pub use traits::{chalk::Interner, TraitEnvironment};
58 pub use walk::TypeWalk;
61 cast::Cast, AdtId, BoundVar, DebruijnIndex, Mutability, Safety, Scalar, TyVariableKind,
64 pub type ForeignDefId = chalk_ir::ForeignDefId<Interner>;
65 pub type AssocTypeId = chalk_ir::AssocTypeId<Interner>;
66 pub type FnDefId = chalk_ir::FnDefId<Interner>;
67 pub type ClosureId = chalk_ir::ClosureId<Interner>;
68 pub type OpaqueTyId = chalk_ir::OpaqueTyId<Interner>;
69 pub type PlaceholderIndex = chalk_ir::PlaceholderIndex;
71 pub type VariableKind = chalk_ir::VariableKind<Interner>;
72 pub type VariableKinds = chalk_ir::VariableKinds<Interner>;
73 pub type CanonicalVarKinds = chalk_ir::CanonicalVarKinds<Interner>;
74 pub type Binders<T> = chalk_ir::Binders<T>;
75 pub type Substitution = chalk_ir::Substitution<Interner>;
76 pub type GenericArg = chalk_ir::GenericArg<Interner>;
77 pub type GenericArgData = chalk_ir::GenericArgData<Interner>;
79 pub type Ty = chalk_ir::Ty<Interner>;
80 pub type TyKind = chalk_ir::TyKind<Interner>;
81 pub type DynTy = chalk_ir::DynTy<Interner>;
82 pub type FnPointer = chalk_ir::FnPointer<Interner>;
83 // pub type FnSubst = chalk_ir::FnSubst<Interner>;
84 pub use chalk_ir::FnSubst;
85 pub type ProjectionTy = chalk_ir::ProjectionTy<Interner>;
86 pub type AliasTy = chalk_ir::AliasTy<Interner>;
87 pub type OpaqueTy = chalk_ir::OpaqueTy<Interner>;
88 pub type InferenceVar = chalk_ir::InferenceVar;
90 pub type Lifetime = chalk_ir::Lifetime<Interner>;
91 pub type LifetimeData = chalk_ir::LifetimeData<Interner>;
92 pub type LifetimeOutlives = chalk_ir::LifetimeOutlives<Interner>;
94 pub type Const = chalk_ir::Const<Interner>;
95 pub type ConstData = chalk_ir::ConstData<Interner>;
96 pub type ConstValue = chalk_ir::ConstValue<Interner>;
97 pub type ConcreteConst = chalk_ir::ConcreteConst<Interner>;
99 pub type ChalkTraitId = chalk_ir::TraitId<Interner>;
101 pub type FnSig = chalk_ir::FnSig<Interner>;
103 pub type InEnvironment<T> = chalk_ir::InEnvironment<T>;
104 pub type DomainGoal = chalk_ir::DomainGoal<Interner>;
105 pub type AliasEq = chalk_ir::AliasEq<Interner>;
106 pub type Solution = chalk_solve::Solution<Interner>;
107 pub type ConstrainedSubst = chalk_ir::ConstrainedSubst<Interner>;
108 pub type Guidance = chalk_solve::Guidance<Interner>;
109 pub type WhereClause = chalk_ir::WhereClause<Interner>;
111 // FIXME: get rid of this
112 pub fn subst_prefix(s: &Substitution, n: usize) -> Substitution {
113 Substitution::from_iter(
115 s.interned()[..std::cmp::min(s.len(&Interner), n)].iter().cloned(),
119 /// Return an index of a parameter in the generic type parameter list by it's id.
120 pub fn param_idx(db: &dyn HirDatabase, id: TypeParamId) -> Option<usize> {
121 generics(db.upcast(), id.parent).param_idx(id)
124 pub fn wrap_empty_binders<T>(value: T) -> Binders<T>
126 T: Fold<Interner, Result = T> + HasInterner<Interner = Interner>,
128 Binders::empty(&Interner, value.shifted_in_from(&Interner, DebruijnIndex::ONE))
131 pub fn make_only_type_binders<T: HasInterner<Interner = Interner>>(
136 VariableKinds::from_iter(
138 std::iter::repeat(chalk_ir::VariableKind::Ty(chalk_ir::TyVariableKind::General))
145 // FIXME: get rid of this
146 pub fn make_canonical<T: HasInterner<Interner = Interner>>(
148 kinds: impl IntoIterator<Item = TyVariableKind>,
150 let kinds = kinds.into_iter().map(|tk| {
151 chalk_ir::CanonicalVarKind::new(
152 chalk_ir::VariableKind::Ty(tk),
153 chalk_ir::UniverseIndex::ROOT,
156 Canonical { value, binders: chalk_ir::CanonicalVarKinds::from_iter(&Interner, kinds) }
159 pub type TraitRef = chalk_ir::TraitRef<Interner>;
161 pub type QuantifiedWhereClause = Binders<WhereClause>;
163 pub type QuantifiedWhereClauses = chalk_ir::QuantifiedWhereClauses<Interner>;
165 pub type Canonical<T> = chalk_ir::Canonical<T>;
167 /// A function signature as seen by type inference: Several parameter types and
169 #[derive(Clone, PartialEq, Eq, Debug)]
170 pub struct CallableSig {
171 params_and_return: Arc<[Ty]>,
175 /// A polymorphic function signature.
176 pub type PolyFnSig = Binders<CallableSig>;
179 pub fn from_params_and_return(mut params: Vec<Ty>, ret: Ty, is_varargs: bool) -> CallableSig {
181 CallableSig { params_and_return: params.into(), is_varargs }
184 pub fn from_fn_ptr(fn_ptr: &FnPointer) -> CallableSig {
186 // FIXME: what to do about lifetime params? -> return PolyFnSig
187 params_and_return: fn_ptr
190 .shifted_out_to(&Interner, DebruijnIndex::ONE)
191 .expect("unexpected lifetime vars in fn ptr")
195 .map(|arg| arg.assert_ty_ref(&Interner).clone())
197 is_varargs: fn_ptr.sig.variadic,
201 pub fn params(&self) -> &[Ty] {
202 &self.params_and_return[0..self.params_and_return.len() - 1]
205 pub fn ret(&self) -> &Ty {
206 &self.params_and_return[self.params_and_return.len() - 1]
210 impl Fold<Interner> for CallableSig {
211 type Result = CallableSig;
215 folder: &mut dyn chalk_ir::fold::Folder<'i, Interner>,
216 outer_binder: DebruijnIndex,
217 ) -> chalk_ir::Fallible<Self::Result>
221 let vec = self.params_and_return.to_vec();
222 let folded = vec.fold_with(folder, outer_binder)?;
223 Ok(CallableSig { params_and_return: folded.into(), is_varargs: self.is_varargs })
227 #[derive(Copy, Clone, PartialEq, Eq, Debug, Hash)]
228 pub enum ImplTraitId {
229 ReturnTypeImplTrait(hir_def::FunctionId, u16),
230 AsyncBlockTypeImplTrait(hir_def::DefWithBodyId, ExprId),
233 #[derive(Clone, PartialEq, Eq, Debug, Hash)]
234 pub struct ReturnTypeImplTraits {
235 pub(crate) impl_traits: Vec<ReturnTypeImplTrait>,
238 #[derive(Clone, PartialEq, Eq, Debug, Hash)]
239 pub(crate) struct ReturnTypeImplTrait {
240 pub(crate) bounds: Binders<Vec<QuantifiedWhereClause>>,
243 pub fn to_foreign_def_id(id: TypeAliasId) -> ForeignDefId {
244 chalk_ir::ForeignDefId(salsa::InternKey::as_intern_id(&id))
247 pub fn from_foreign_def_id(id: ForeignDefId) -> TypeAliasId {
248 salsa::InternKey::from_intern_id(id.0)
251 pub fn to_assoc_type_id(id: TypeAliasId) -> AssocTypeId {
252 chalk_ir::AssocTypeId(salsa::InternKey::as_intern_id(&id))
255 pub fn from_assoc_type_id(id: AssocTypeId) -> TypeAliasId {
256 salsa::InternKey::from_intern_id(id.0)
259 pub fn from_placeholder_idx(db: &dyn HirDatabase, idx: PlaceholderIndex) -> TypeParamId {
260 assert_eq!(idx.ui, chalk_ir::UniverseIndex::ROOT);
261 let interned_id = salsa::InternKey::from_intern_id(salsa::InternId::from(idx.idx));
262 db.lookup_intern_type_param_id(interned_id)
265 pub fn to_placeholder_idx(db: &dyn HirDatabase, id: TypeParamId) -> PlaceholderIndex {
266 let interned_id = db.intern_type_param_id(id);
268 ui: chalk_ir::UniverseIndex::ROOT,
269 idx: salsa::InternKey::as_intern_id(&interned_id).as_usize(),
273 pub fn lt_from_placeholder_idx(db: &dyn HirDatabase, idx: PlaceholderIndex) -> LifetimeParamId {
274 assert_eq!(idx.ui, chalk_ir::UniverseIndex::ROOT);
275 let interned_id = salsa::InternKey::from_intern_id(salsa::InternId::from(idx.idx));
276 db.lookup_intern_lifetime_param_id(interned_id)
279 pub fn const_from_placeholder_idx(db: &dyn HirDatabase, idx: PlaceholderIndex) -> ConstParamId {
280 assert_eq!(idx.ui, chalk_ir::UniverseIndex::ROOT);
281 let interned_id = salsa::InternKey::from_intern_id(salsa::InternId::from(idx.idx));
282 db.lookup_intern_const_param_id(interned_id)
285 pub fn to_chalk_trait_id(id: TraitId) -> ChalkTraitId {
286 chalk_ir::TraitId(salsa::InternKey::as_intern_id(&id))
289 pub fn from_chalk_trait_id(id: ChalkTraitId) -> TraitId {
290 salsa::InternKey::from_intern_id(id.0)
293 pub fn static_lifetime() -> Lifetime {
294 LifetimeData::Static.intern(&Interner)
297 pub fn dummy_usize_const() -> Const {
298 let usize_ty = chalk_ir::TyKind::Scalar(Scalar::Uint(UintTy::Usize)).intern(&Interner);
299 chalk_ir::ConstData {
301 value: chalk_ir::ConstValue::Concrete(chalk_ir::ConcreteConst { interned: () }),
306 pub(crate) fn fold_free_vars<T: HasInterner<Interner = Interner> + Fold<Interner>>(
308 f: impl FnMut(BoundVar, DebruijnIndex) -> Ty,
310 use chalk_ir::{fold::Folder, Fallible};
311 struct FreeVarFolder<F>(F);
312 impl<'i, F: FnMut(BoundVar, DebruijnIndex) -> Ty + 'i> Folder<'i, Interner> for FreeVarFolder<F> {
313 fn as_dyn(&mut self) -> &mut dyn Folder<'i, Interner> {
317 fn interner(&self) -> &'i Interner {
324 outer_binder: DebruijnIndex,
326 Ok(self.0(bound_var, outer_binder))
329 t.fold_with(&mut FreeVarFolder(f), DebruijnIndex::INNERMOST).expect("fold failed unexpectedly")