Switch to hashbrown's RawTable internally

Author: cuviper

Cargo.toml

@@ -35,6 +35,11 @@ autocfg = "1"
 serde = { version = "1.0", optional = true, default-features = false }
 rayon = { version = "1.0", optional = true }
 
+[dependencies.hashbrown]
+version = "0.7"
+default-features = false
+features = ["inline-more", "raw"]
+
 [dev-dependencies]
 itertools = "0.8"
 rand = {version = "0.7", features = ["small_rng"] }

README.rst

@@ -15,8 +15,7 @@ indexmap
 .. |rustc| image:: https://img.shields.io/badge/rust-1.18%2B-orange.svg
 .. _rustc: https://img.shields.io/badge/rust-1.18%2B-orange.svg
 
-A safe, pure-Rust hash table which preserves (in a limited sense) insertion
-order.
+A pure-Rust hash table which preserves (in a limited sense) insertion order.
 
 This crate implements compact map and set data-structures,
 where the iteration order of the keys is independent from their hash or
@@ -45,11 +44,6 @@ was indexmap, a hash table that has following properties:
   - It's the usual backwards shift deletion, but only on the index vector, so
     it's cheaper because it's moving less memory around.
 
-Does not implement (Yet)
-------------------------
-
-- ``.reserve()`` exists but does not have a complete implementation
-
 Performance
 -----------
 

src/lib.rs

@@ -53,9 +53,10 @@
 //! [def]: map/struct.IndexMap.html#impl-Default
 
 #[cfg(not(has_std))]
-#[macro_use(vec)]
 extern crate alloc;
 
+extern crate hashbrown;
+
 #[cfg(not(has_std))]
 pub(crate) mod std {
     pub use core::*;
@@ -102,8 +103,8 @@ struct HashValue(usize);
 
 impl HashValue {
     #[inline(always)]
-    fn get(self) -> usize {
-        self.0
+    fn get(self) -> u64 {
+        self.0 as u64
     }
 }