namespace Azure.Storage.Common { internal static class Optional { public static bool IsCollectionDefined<T>(IEnumerable<T> collection); public static bool IsCollectionDefined<TKey, TValue>(IDictionary<TKey, TValue> collection); public static bool IsCollectionDefined<TKey, TValue>(IReadOnlyDictionary<TKey, TValue> collection); public static bool IsDefined<T>(T? value) where T : struct; public static bool IsDefined(object value); public static bool IsDefined(JsonElement value); public static bool IsDefined(string value); } }