diff --git a/digest.go b/digest.go
index 518b5e7..41239e7 100644
--- a/digest.go
+++ b/digest.go
@@ -80,7 +80,10 @@ var (
 // be returned if the format is invalid.
 func Parse(s string) (Digest, error) {
 	d := Digest(s)
-	return d, d.Validate()
+	if err := d.Validate(); err != nil {
+		return "", err
+	}
+	return d, nil
 }
 
 // FromReader consumes the content of rd until io.EOF, returning canonical digest.
@@ -137,11 +140,21 @@ func (d Digest) Encoded() string {
 	return string(d[d.sepIndex()+1:])
 }
 
-// Hex is deprecated. Please use Digest.Encoded.
+// IsIdenticalTo compares this digest to any other, inclusive of the hashing algorithm used
+func (d Digest) IsIdenticalTo(o Digest) bool {
+	return string(d) == string(o)
+}
+
+// Deprecated: Hex has been deprecated in favor of Digest.Encoded
 func (d Digest) Hex() string {
 	return d.Encoded()
 }
 
+// IsEmpty does what it says (an empty digest is an empty string)
+func (d Digest) IsEmpty() bool {
+	return len(d.String()) == 0
+}
+
 func (d Digest) String() string {
 	return string(d)
 }
diff --git a/digestset/set.go b/digestset/set.go
index 71f2418..3e1cc9c 100644
--- a/digestset/set.go
+++ b/digestset/set.go
@@ -92,13 +92,14 @@ func (dst *Set) Lookup(d string) (digest.Digest, error) {
 		alg        digest.Algorithm
 		hex        string
 	)
-	dgst, err := digest.Parse(d)
+	_, err := digest.Parse(d)
 	if err == digest.ErrDigestInvalidFormat {
 		hex = d
 		searchFunc = func(i int) bool {
 			return dst.entries[i].val >= d
 		}
 	} else {
+		dgst := digest.Digest(d)
 		hex = dgst.Hex()
 		alg = dgst.Algorithm()
 		searchFunc = func(i int) bool {