Tracked memoization

3 files changed, 1 insertions, 66 deletions

diff --git a/src/util/buffer.rs b/src/util/buffer.rs
index daee86f9..766b2084 100644
--- a/src/util/buffer.rs
+++ b/src/util/buffer.rs
@@ -2,7 +2,7 @@ use std::fmt::{self, Debug, Formatter};
 use std::ops::Deref;
 use std::sync::Arc;
 
-use super::Prehashed;
+use comemo::Prehashed;
 
 /// A shared buffer that is cheap to clone and hash.
 #[derive(Clone, Hash, Eq, PartialEq)]
diff --git a/src/util/hash.rs b/src/util/hash.rs
deleted file mode 100644
index 79455918..00000000
--- a/src/util/hash.rs
+++ /dev/null
@@ -1,63 +0,0 @@
-use std::any::Any;
-use std::fmt::{self, Debug, Formatter};
-use std::hash::{Hash, Hasher};
-use std::ops::Deref;
-
-/// A wrapper around a type that precomputes its hash.
-#[derive(Copy, Clone)]
-pub struct Prehashed<T: ?Sized> {
-    /// The precomputed hash.
-    hash: u64,
-    /// The wrapped item.
-    item: T,
-}
-
-impl<T: Hash + 'static> Prehashed<T> {
-    /// Compute an item's hash and wrap it.
-    pub fn new(item: T) -> Self {
-        Self {
-            hash: {
-                // Also hash the TypeId because the type might be converted
-                // through an unsized coercion.
-                let mut state = fxhash::FxHasher64::default();
-                item.type_id().hash(&mut state);
-                item.hash(&mut state);
-                state.finish()
-            },
-            item,
-        }
-    }
-
-    /// Return the wrapped value.
-    pub fn into_iter(self) -> T {
-        self.item
-    }
-}
-
-impl<T: ?Sized> Deref for Prehashed<T> {
-    type Target = T;
-
-    fn deref(&self) -> &Self::Target {
-        &self.item
-    }
-}
-
-impl<T: Debug + ?Sized> Debug for Prehashed<T> {
-    fn fmt(&self, f: &mut Formatter) -> fmt::Result {
-        self.item.fmt(f)
-    }
-}
-
-impl<T: ?Sized> Hash for Prehashed<T> {
-    fn hash<H: Hasher>(&self, state: &mut H) {
-        state.write_u64(self.hash);
-    }
-}
-
-impl<T: Eq + ?Sized> Eq for Prehashed<T> {}
-
-impl<T: ?Sized> PartialEq for Prehashed<T> {
-    fn eq(&self, other: &Self) -> bool {
-        self.hash == other.hash
-    }
-}
diff --git a/src/util/mod.rs b/src/util/mod.rs
index 4a48b1d3..d549fc5f 100644
--- a/src/util/mod.rs
+++ b/src/util/mod.rs
@@ -3,11 +3,9 @@
 #[macro_use]
 mod eco;
 mod buffer;
-mod hash;
 
 pub use buffer::Buffer;
 pub use eco::EcoString;
-pub use hash::Prehashed;
 
 use std::any::TypeId;
 use std::fmt::{self, Debug, Formatter};