add OrElse method

gonull.go

@@ -149,6 +149,15 @@ func (n Nullable[T]) MarshalJSON() ([]byte, error) {
 	return json.Marshal(n.Val)
 }
 
+// OrElse returns the underlying Val if valid otherwise returns the provided defaultVal
+func (n Nullable[T]) OrElse(defaultVal T) T {
+	if n.Valid {
+		return n.Val
+	} else {
+		return defaultVal
+	}
+}
+
 // zeroValue is a helper function that returns the zero value for the generic type T.
 // It is used to set the zero value for the Val field of the Nullable struct when the value is nil.
 func zeroValue[T any]() T {

gonull_test.go

@@ -497,6 +497,15 @@ func TestValuerAndScanner(t *testing.T) {
 	}, scannerNullableUnsupported)
 }
 
+func TestNullableOrElse(t *testing.T) {
+	value := "hello"
+	nonEmpty := NewNullable(value)
+	assert.Equal(t, value, nonEmpty.OrElse("world"))
+
+	var empty Nullable[string]
+	assert.Equal(t, "world", empty.OrElse("world"))
+}
+
 type customValuer struct {
 	value any
 	err   error