Untangle caching code

2 files changed, 3 insertions, 4 deletions

diff --git a/dhall/src/syntax/ast/expr.rs b/dhall/src/syntax/ast/expr.rs
index b1a978f..eba2735 100644
--- a/dhall/src/syntax/ast/expr.rs
+++ b/dhall/src/syntax/ast/expr.rs
@@ -178,10 +178,9 @@ impl Expr {
     }
 
     // Compute the sha256 hash of the binary form of the expression.
-    pub fn hash(&self) -> Result<Box<[u8]>, Error> {
-        use sha2::Digest;
+    pub fn sha256_hash(&self) -> Result<Box<[u8]>, Error> {
         let data = binary::encode(self)?;
-        Ok(sha2::Sha256::digest(&data).as_slice().into())
+        Ok(crate::utils::sha256_hash(&data))
     }
 }
 
diff --git a/dhall/src/syntax/ast/import.rs b/dhall/src/syntax/ast/import.rs
index c45fe51..69f4021 100644
--- a/dhall/src/syntax/ast/import.rs
+++ b/dhall/src/syntax/ast/import.rs
@@ -52,7 +52,7 @@ pub enum ImportMode {
 
 #[derive(Debug, Clone, PartialEq, Eq, Hash)]
 pub enum Hash {
-    SHA256(Vec<u8>),
+    SHA256(Box<[u8]>),
 }
 
 /// Reference to an external resource