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stacker/src/arena_hashmap.rs

@@ -10,6 +10,10 @@ use crate::shared_arena_hashmap::SharedArenaHashMap;
 /// The quirky API has the benefit of avoiding
 /// the computation of the hash of the key twice,
 /// or copying the key as long as there is no insert.
+///
+/// ArenaHashMap is like SharedArenaHashMap but takes ownership
+/// of the memory arena. The memory arena stores the serialized
+/// keys and values.
 pub struct ArenaHashMap {
     shared_arena_hashmap: SharedArenaHashMap,
     pub memory_arena: MemoryArena,

stacker/src/shared_arena_hashmap.rs

@@ -56,6 +56,10 @@ impl KeyValue {
 /// The quirky API has the benefit of avoiding
 /// the computation of the hash of the key twice,
 /// or copying the key as long as there is no insert.
+///
+/// SharedArenaHashMap is like ArenaHashMap but does the memory arena
+/// gets passed as an argument to the methods.
+/// So one MemoryArena can be shared with multiple SharedArenaHashMap.
 pub struct SharedArenaHashMap {
     table: Vec<KeyValue>,
     mask: usize,