Unnamed repository; edit this file 'description' to name the repository.
Diffstat (limited to 'crates/hir-ty/src/utils.rs')
| -rw-r--r-- | crates/hir-ty/src/utils.rs | 36 |
1 files changed, 34 insertions, 2 deletions
diff --git a/crates/hir-ty/src/utils.rs b/crates/hir-ty/src/utils.rs index 3b2a726688..aa40d08479 100644 --- a/crates/hir-ty/src/utils.rs +++ b/crates/hir-ty/src/utils.rs @@ -23,10 +23,11 @@ use hir_expand::name::Name; use intern::Interned; use rustc_hash::FxHashSet; use smallvec::{smallvec, SmallVec}; +use stdx::never; use crate::{ - db::HirDatabase, ChalkTraitId, Interner, Substitution, TraitRef, TraitRefExt, Ty, TyExt, - WhereClause, + db::HirDatabase, ChalkTraitId, GenericArg, Interner, Substitution, TraitRef, TraitRefExt, Ty, + TyExt, WhereClause, }; pub(crate) fn fn_traits( @@ -176,6 +177,37 @@ pub(crate) fn generics(db: &dyn DefDatabase, def: GenericDefId) -> Generics { Generics { def, params: db.generic_params(def), parent_generics } } +/// It is a bit different from the rustc equivalent. Currently it stores: +/// - 0: the function signature, encoded as a function pointer type +/// - 1..n: generics of the parent +/// +/// and it doesn't store the closure types and fields. +/// +/// Codes should not assume this ordering, and should always use methods available +/// on this struct for retriving, and `TyBuilder::substs_for_closure` for creating. +pub(crate) struct ClosureSubst<'a>(pub(crate) &'a Substitution); + +impl<'a> ClosureSubst<'a> { + pub(crate) fn parent_subst(&self) -> &'a [GenericArg] { + match self.0.as_slice(Interner) { + [_, x @ ..] => x, + _ => { + never!("Closure missing parameter"); + &[] + } + } + } + + pub(crate) fn sig_ty(&self) -> &'a Ty { + match self.0.as_slice(Interner) { + [x, ..] => x.assert_ty_ref(Interner), + _ => { + unreachable!("Closure missing sig_ty parameter"); + } + } + } +} + #[derive(Debug)] pub(crate) struct Generics { def: GenericDefId, |