1 files changed, 6 insertions, 9 deletions
diff --git a/src/libutil/hash.hh b/src/libutil/hash.hh
index e4abe72ce..a55295912 100644
--- a/src/libutil/hash.hh
+++ b/src/libutil/hash.hh
@@ -10,7 +10,7 @@ namespace nix {
 MakeError(BadHash, Error);
 
 
-enum HashType : char { htMD5, htSHA1, htSHA256, htSHA512 };
+enum HashType : char { htMD5 = 42, htSHA1, htSHA256, htSHA512 };
 
 
 const int md5HashSize = 16;
@@ -25,14 +25,11 @@ enum Base : int { Base64, Base32, Base16, SRI };
 
 struct Hash
 {
-    static const unsigned int maxHashSize = 64;
-    unsigned int hashSize = 0;
-    unsigned char hash[maxHashSize] = {};
+    constexpr static size_t maxHashSize = 64;
+    size_t hashSize = 0;
+    uint8_t hash[maxHashSize] = {};
 
-    std::optional<HashType> type = {};
-
-    /* Create an unset hash object. */
-    Hash() { };
+    HashType type;
 
     /* Create a zero-filled hash object. */
     Hash(HashType type) : type(type) { init(); };
@@ -105,7 +102,7 @@ Hash newHashAllowEmpty(std::string hashStr, std::optional<HashType> ht);
 string printHash16or32(const Hash & hash);
 
 /* Compute the hash of the given string. */
-Hash hashString(HashType ht, const string & s);
+Hash hashString(HashType ht, std::string_view s);
 
 /* Compute the hash of the given file. */
 Hash hashFile(HashType ht, const Path & path);