Embelish documentation of new Hash functions

src/libutil/hash.hh

@@ -36,21 +36,26 @@ struct Hash
     /* Create a zero-filled hash object. */
     Hash(HashType type);
 
-    /* Initialize the hash from a string representation, in the format
+    /* Parse the hash from a string representation in the format
        "[<type>:]<base16|base32|base64>" or "<type>-<base64>" (a
        Subresource Integrity hash expression). If the 'type' argument
        is not present, then the hash type must be specified in the
        string. */
     static Hash parseAny(std::string_view s, std::optional<HashType> type);
-    /* hash type must be part of string */
+
+    /* Parse a hash from a string representation like the above, except the
+       type prefix is mandatory is there is no separate arguement. */
     static Hash parseAnyPrefixed(std::string_view s);
-    /* prefix parsed separately; non SRI hash */
+
+    /* Parse a plain hash that musst not have any prefix indicating the type.
+       The type is passed in to disambiguate. */
     static Hash parseNonSRIUnprefixed(std::string_view s, HashType type);
 
     static Hash parseSRI(std::string_view original);
 
 private:
-    // type must be provided, s must not include <type> prefix
+    /* The type must be provided, the string view must not include <type>
+       prefix. `isSRI` helps disambigate the various base-* encodings. */
     Hash(std::string_view s, HashType type, bool isSRI);
 
 public: