New upstream version 1.52.0~beta.3+dfsg1

[rustc.git] / compiler / rustc_ast / src / node_id.rs

diff --git a/compiler/rustc_ast/src/node_id.rs b/compiler/rustc_ast/src/node_id.rs
index 6e7d2bab2877eadc77f0a756cf38598afe0984a9..d20bace6088826890e2ecfb23df75637ff2c209f 100644 (file)
--- a/compiler/rustc_ast/src/node_id.rs
+++ b/compiler/rustc_ast/src/node_id.rs
@@ -2,6 +2,12 @@ use rustc_span::ExpnId;
 use std::fmt;
 
 rustc_index::newtype_index! {
+    /// Identifies an AST node.
+    ///
+    /// This identifies top-level definitions, expressions, and everything in between.
+    /// This is later turned into [`DefId`] and `HirId` for the HIR.
+    ///
+    /// [`DefId`]: rustc_span::def_id::DefId
     pub struct NodeId {
         DEBUG_FORMAT = "NodeId({})"
     }
@@ -9,12 +15,12 @@ rustc_index::newtype_index! {
 
 rustc_data_structures::define_id_collections!(NodeMap, NodeSet, NodeId);
 
-/// `NodeId` used to represent the root of the crate.
+/// The [`NodeId`] used to represent the root of the crate.
 pub const CRATE_NODE_ID: NodeId = NodeId::from_u32(0);
 
-/// When parsing and doing expansions, we initially give all AST nodes this AST
-/// node value. Then later, during expansion, we renumber them to have small,
-/// positive ids.
+/// When parsing and at the beginning of doing expansions, we initially give all AST nodes
+/// this dummy AST [`NodeId`]. Then, during a later phase of expansion, we renumber them
+/// to have small, positive IDs.
 pub const DUMMY_NODE_ID: NodeId = NodeId::MAX;
 
 impl NodeId {