IndexMap::new() is now a const-fn

Author: korken89

CHANGELOG.md

@@ -18,6 +18,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 - `Pool` and `MPMC` now works on `thumbv6m`
 - [breaking-change] `String` has had `utf8` related methods removed as this can be done via `str`
 - [breaking-change] No data structures implement `AsSlice` traits any more, now using `AsRef` and `AsMut`
+- `IndexMap::new()` is now a `const-fn`
 
 ## [v0.6.1] - 2021-03-02
 

Cargo.toml

@@ -36,7 +36,7 @@ scoped_threadpool = "0.1.8"
 atomic-polyfill = "0.1.2"
 
 [dependencies]
-hash32 = "0.1.0"
+hash32 = "0.2.1"
 
 [dependencies.serde]
 version = "1"

src/indexmap.rs

@@ -360,25 +360,16 @@ where
 ///     println!("{}: \"{}\"", book, review);
 /// }
 /// ```
-pub struct IndexMap<K, V, S, const N: usize>
-where
-    K: Eq + Hash,
-{
+pub struct IndexMap<K, V, S, const N: usize> {
     core: CoreMap<K, V, N>,
     build_hasher: S,
 }
 
-impl<K, V, S, const N: usize> IndexMap<K, V, BuildHasherDefault<S>, N>
-where
-    K: Eq + Hash,
-    S: Default + Hasher,
-{
+impl<K, V, S, const N: usize> IndexMap<K, V, BuildHasherDefault<S>, N> {
     /// Creates an empty `IndexMap`.
-    ///
-    /// **NOTE** This constructor will become a `const fn` in the future
-    pub fn new() -> Self {
+    pub const fn new() -> Self {
         IndexMap {
-            build_hasher: BuildHasherDefault::default(),
+            build_hasher: BuildHasherDefault::new(),
             core: CoreMap::new(),
         }
     }
@@ -737,7 +728,6 @@ where
     K: Eq + Hash + Borrow<Q>,
     Q: ?Sized + Eq + Hash,
     S: BuildHasher,
-    //   N: ArrayLength<Bucket<K, V>> + ArrayLength<Option<Pos>>,
 {
     type Output = V;
 
@@ -751,7 +741,6 @@ where
     K: Eq + Hash + Borrow<Q>,
     Q: ?Sized + Eq + Hash,
     S: BuildHasher,
-    //   N: ArrayLength<Bucket<K, V>> + ArrayLength<Option<Pos>>,
 {
     fn index_mut(&mut self, key: &Q) -> &mut V {
         self.get_mut(key).expect("key not found")
@@ -763,7 +752,6 @@ where
     K: Eq + Hash + Clone,
     V: Clone,
     S: Clone,
-    //    N: ArrayLength<Bucket<K, V>> + ArrayLength<Option<Pos>>,
 {
     fn clone(&self) -> Self {
         Self {
@@ -778,7 +766,6 @@ where
     K: Eq + Hash + fmt::Debug,
     V: fmt::Debug,
     S: BuildHasher,
-    //    N: ArrayLength<Bucket<K, V>> + ArrayLength<Option<Pos>>,
 {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         f.debug_map().entries(self.iter()).finish()
@@ -789,7 +776,6 @@ impl<K, V, S, const N: usize> Default for IndexMap<K, V, S, N>
 where
     K: Eq + Hash,
     S: BuildHasher + Default,
-    // N: ArrayLength<Bucket<K, V>> + ArrayLength<Option<Pos>>,
 {
     fn default() -> Self {
         IndexMap {

src/string.rs

@@ -389,38 +389,6 @@ impl<const N1: usize, const N2: usize> PartialEq<String<N2>> for String<N1> {
     }
 }
 
-// macro_rules! impl_eq {
-//     ($lhs:ty, $rhs:ty) => {
-//         impl<'a, 'b, N> PartialEq<$rhs> for $lhs
-//         where
-//             N: ArrayLength<u8>,
-//         {
-//             #[inline]
-//             fn eq(&self, other: &$rhs) -> bool {
-//                 str::eq(&self[..], &other[..])
-//             }
-//             #[inline]
-//             fn ne(&self, other: &$rhs) -> bool {
-//                 str::ne(&self[..], &other[..])
-//             }
-//         }
-
-//         impl<'a, 'b, N> PartialEq<$lhs> for $rhs
-//         where
-//             N: ArrayLength<u8>,
-//         {
-//             #[inline]
-//             fn eq(&self, other: &$lhs) -> bool {
-//                 str::eq(&self[..], &other[..])
-//             }
-//             #[inline]
-//             fn ne(&self, other: &$lhs) -> bool {
-//                 str::ne(&self[..], &other[..])
-//             }
-//         }
-//     };
-// }
-
 // String<N> == str
 impl<const N: usize> PartialEq<str> for String<N> {
     #[inline]