Minor doc improvements

[rust.git] / src / librustc / ty / context.rs

diff --git a/src/librustc/ty/context.rs b/src/librustc/ty/context.rs
index 1bccd05af83237f82e1b1823d57bea542ca8d20e..1a9f86306325f1857a5eded35dce12c4215a7433 100644 (file)
--- a/src/librustc/ty/context.rs
+++ b/src/librustc/ty/context.rs
@@ -50,7 +50,8 @@
 use ty::steal::Steal;
 use ty::BindingMode;
 use ty::CanonicalTy;
-use util::nodemap::{DefIdSet, ItemLocalMap};
+use ty::CanonicalPolyFnSig;
+use util::nodemap::{DefIdMap, DefIdSet, ItemLocalMap};
 use util::nodemap::{FxHashMap, FxHashSet};
 use smallvec::SmallVec;
 use rustc_data_structures::stable_hasher::{HashStable, hash_stable_hashmap,
@@ -89,13 +90,14 @@ pub struct AllArenas<'tcx> {
 impl<'tcx> AllArenas<'tcx> {
     pub fn new() -> Self {
         AllArenas {
-            global: WorkerLocal::new(|_| GlobalArenas::new()),
-            interner: SyncDroplessArena::new(),
+            global: WorkerLocal::new(|_| GlobalArenas::default()),
+            interner: SyncDroplessArena::default(),
         }
     }
 }
 
 /// Internal storage
+#[derive(Default)]
 pub struct GlobalArenas<'tcx> {
     // internings
     layout: TypedArena<LayoutDetails>,
@@ -111,21 +113,6 @@ pub struct GlobalArenas<'tcx> {
     const_allocs: TypedArena<interpret::Allocation>,
 }
 
-impl<'tcx> GlobalArenas<'tcx> {
-    pub fn new() -> GlobalArenas<'tcx> {
-        GlobalArenas {
-            layout: TypedArena::new(),
-            generics: TypedArena::new(),
-            trait_def: TypedArena::new(),
-            adt_def: TypedArena::new(),
-            steal_mir: TypedArena::new(),
-            mir: TypedArena::new(),
-            tables: TypedArena::new(),
-            const_allocs: TypedArena::new(),
-        }
-    }
-}
-
 type InternedSet<'tcx, T> = Lock<FxHashSet<Interned<'tcx, T>>>;
 
 pub struct CtxtInterners<'tcx> {
@@ -358,10 +345,6 @@ pub struct TypeckTables<'tcx> {
     /// belongs, but it may not exist if it's a tuple field (`tuple.0`).
     field_indices: ItemLocalMap<usize>,
 
-    /// Stores the canonicalized types provided by the user. See also
-    /// `AscribeUserType` statement in MIR.
-    user_provided_tys: ItemLocalMap<CanonicalTy<'tcx>>,
-
     /// Stores the types for various nodes in the AST.  Note that this table
     /// is not guaranteed to be populated until after typeck.  See
     /// typeck::check::fn_ctxt for details.
@@ -373,6 +356,14 @@ pub struct TypeckTables<'tcx> {
     /// other items.
     node_substs: ItemLocalMap<&'tcx Substs<'tcx>>,
 
+    /// Stores the canonicalized types provided by the user. See also
+    /// `AscribeUserType` statement in MIR.
+    user_provided_tys: ItemLocalMap<CanonicalTy<'tcx>>,
+
+    /// Stores the canonicalized types provided by the user. See also
+    /// `AscribeUserType` statement in MIR.
+    pub user_provided_sigs: DefIdMap<CanonicalPolyFnSig<'tcx>>,
+
     /// Stores the substitutions that the user explicitly gave (if any)
     /// attached to `id`. These will not include any inferred
     /// values. The canonical form is used to capture things like `_`
@@ -456,21 +447,22 @@ pub fn empty(local_id_root: Option<DefId>) -> TypeckTables<'tcx> {
             type_dependent_defs: ItemLocalMap(),
             field_indices: ItemLocalMap(),
             user_provided_tys: ItemLocalMap(),
+            user_provided_sigs: Default::default(),
             node_types: ItemLocalMap(),
             node_substs: ItemLocalMap(),
             user_substs: ItemLocalMap(),
             adjustments: ItemLocalMap(),
             pat_binding_modes: ItemLocalMap(),
             pat_adjustments: ItemLocalMap(),
-            upvar_capture_map: FxHashMap(),
+            upvar_capture_map: Default::default(),
             closure_kind_origins: ItemLocalMap(),
             liberated_fn_sigs: ItemLocalMap(),
             fru_field_types: ItemLocalMap(),
             cast_kinds: ItemLocalMap(),
             used_trait_imports: Lrc::new(DefIdSet()),
             tainted_by_errors: false,
-            free_region_map: FreeRegionMap::new(),
-            concrete_existential_types: FxHashMap(),
+            free_region_map: Default::default(),
+            concrete_existential_types: Default::default(),
         }
     }
 
@@ -565,7 +557,7 @@ pub fn node_substs_mut(&mut self) -> LocalTableInContextMut<'_, &'tcx Substs<'tc
 
     pub fn node_substs(&self, id: hir::HirId) -> &'tcx Substs<'tcx> {
         validate_hir_id_for_typeck_tables(self.local_id_root, id, false);
-        self.node_substs.get(&id.local_id).cloned().unwrap_or(Substs::empty())
+        self.node_substs.get(&id.local_id).cloned().unwrap_or_else(|| Substs::empty())
     }
 
     pub fn node_substs_opt(&self, id: hir::HirId) -> Option<&'tcx Substs<'tcx>> {
@@ -762,6 +754,7 @@ fn hash_stable<W: StableHasherResult>(&self,
             ref type_dependent_defs,
             ref field_indices,
             ref user_provided_tys,
+            ref user_provided_sigs,
             ref node_types,
             ref node_substs,
             ref user_substs,
@@ -785,6 +778,7 @@ fn hash_stable<W: StableHasherResult>(&self,
             type_dependent_defs.hash_stable(hcx, hasher);
             field_indices.hash_stable(hcx, hasher);
             user_provided_tys.hash_stable(hcx, hasher);
+            user_provided_sigs.hash_stable(hcx, hasher);
             node_types.hash_stable(hcx, hasher);
             node_substs.hash_stable(hcx, hasher);
             user_substs.hash_stable(hcx, hasher);
@@ -937,7 +931,9 @@ pub struct GlobalCtxt<'tcx> {
 
     maybe_unused_trait_imports: FxHashSet<DefId>,
     maybe_unused_extern_crates: Vec<(DefId, Span)>,
-    pub extern_prelude: FxHashSet<ast::Name>,
+    /// Extern prelude entries. The value is `true` if the entry was introduced
+    /// via `extern crate` item and not `--extern` option or compiler built-in.
+    pub extern_prelude: FxHashMap<ast::Name, bool>,
 
     // Internal cache for metadata decoding. No need to track deps on this.
     pub rcache: Lock<FxHashMap<ty::CReaderCacheKey, Ty<'tcx>>>,
@@ -1190,7 +1186,7 @@ pub fn create_and_enter<F, R>(s: &'tcx Session,
             None
         };
 
-        let mut trait_map: FxHashMap<_, Lrc<FxHashMap<_, _>>> = FxHashMap();
+        let mut trait_map: FxHashMap<_, Lrc<FxHashMap<_, _>>> = FxHashMap::default();
         for (k, v) in resolutions.trait_map {
             let hir_id = hir.node_to_hir_id(k);
             let map = trait_map.entry(hir_id.owner).or_default();
@@ -1231,14 +1227,14 @@ pub fn create_and_enter<F, R>(s: &'tcx Session,
                 extern_providers,
                 on_disk_query_result_cache,
             ),
-            rcache: Lock::new(FxHashMap()),
-            selection_cache: traits::SelectionCache::new(),
-            evaluation_cache: traits::EvaluationCache::new(),
+            rcache: Default::default(),
+            selection_cache: Default::default(),
+            evaluation_cache: Default::default(),
             crate_name: Symbol::intern(crate_name),
             data_layout,
-            layout_interner: Lock::new(FxHashSet()),
-            stability_interner: Lock::new(FxHashSet()),
-            allocation_interner: Lock::new(FxHashSet()),
+            layout_interner: Default::default(),
+            stability_interner: Default::default(),
+            allocation_interner: Default::default(),
             alloc_map: Lock::new(interpret::AllocMap::new()),
             tx_to_llvm_workers: Lock::new(tx),
             output_filenames: Arc::new(output_filenames.clone()),