diff --git a/fragment.go b/fragment.go
index 6945261f5..f7b388855 100644
--- a/fragment.go
+++ b/fragment.go
@@ -326,7 +326,7 @@ func (f *Fragment) SetBit(bitmapID, profileID uint64, t *time.Time, q TimeQuantu
 
 func (f *Fragment) setBit(bitmapID, profileID uint64) (changed bool, bool error) {
 	// Determine the position of the bit in the storage.
-	ret := false
+	changed = false
 	pos, err := f.pos(bitmapID, profileID)
 	if err != nil {
 		return false, err
@@ -334,15 +334,15 @@ func (f *Fragment) setBit(bitmapID, profileID uint64) (changed bool, bool error)
 
 	// Write to storage.
 
-	if ret, err = f.storage.Add(pos); err != nil {
+	if changed, err = f.storage.Add(pos); err != nil {
 		return false, err
 	}
 
 	// Update the cache.
 	if f.bitmap(bitmapID).setBit(profileID) {
-		ret = true
+		changed = true
 	}
-	return ret, nil
+	return changed, nil
 
 }
 
diff --git a/roaring/roaring.go b/roaring/roaring.go
index 020bbf62a..a87d4f5c1 100644
--- a/roaring/roaring.go
+++ b/roaring/roaring.go
@@ -41,8 +41,8 @@ func NewBitmap(a ...uint64) *Bitmap {
 }
 
 // Add adds values to the bitmap.
-func (b *Bitmap) Add(a ...uint64) (bool, error) {
-	ret := false
+func (b *Bitmap) Add(a ...uint64) (changed bool, err error) {
+	changed = false
 	for _, v := range a {
 		// Create an add operation.
 		op := &op{typ: opTypeAdd, value: v}
@@ -54,12 +54,12 @@ func (b *Bitmap) Add(a ...uint64) (bool, error) {
 
 		// Apply to the in-memory bitmap.
 		if op.apply(b) {
-			ret = true
+			changed = true
 
 		}
 	}
 
-	return ret, nil
+	return changed, nil
 }
 
 func (b *Bitmap) add(v uint64) bool {
@@ -86,8 +86,8 @@ func (b *Bitmap) Contains(v uint64) bool {
 }
 
 // Remove removes values from the bitmap.
-func (b *Bitmap) Remove(a ...uint64) (bool, error) {
-	ret := false
+func (b *Bitmap) Remove(a ...uint64) (changed bool, err error) {
+	changed = false
 	for _, v := range a {
 		// Create an add operation.
 		op := &op{typ: opTypeRemove, value: v}
@@ -99,10 +99,10 @@ func (b *Bitmap) Remove(a ...uint64) (bool, error) {
 
 		// Apply operation to the bitmap.
 		if op.apply(b) {
-			ret = true
+			changed = true
 		}
 	}
-	return ret, nil
+	return changed, nil
 }
 
 func (b *Bitmap) remove(v uint64) bool {