Optional
using System.Collections.Generic;
using System.Text.Json;
namespace Azure.Storage.Common
{
    internal static class Optional
    {
        public static bool IsCollectionDefined<T>(IEnumerable<T> collection)
        {
            ChangeTrackingList<T> changeTrackingList = collection as ChangeTrackingList<T>;
            if (changeTrackingList != null)
                return !changeTrackingList.IsUndefined;
            return true;
        }
        public static bool IsCollectionDefined<TKey, TValue>(IDictionary<TKey, TValue> collection)
        {
            ChangeTrackingDictionary<TKey, TValue> changeTrackingDictionary = collection as ChangeTrackingDictionary<TKey, TValue>;
            if (changeTrackingDictionary != null)
                return !changeTrackingDictionary.IsUndefined;
            return true;
        }
        public static bool IsCollectionDefined<TKey, TValue>(IReadOnlyDictionary<TKey, TValue> collection)
        {
            ChangeTrackingDictionary<TKey, TValue> changeTrackingDictionary = collection as ChangeTrackingDictionary<TKey, TValue>;
            if (changeTrackingDictionary != null)
                return !changeTrackingDictionary.IsUndefined;
            return true;
        }
        public static bool IsDefined<T>(T? value) where T : struct
        {
            return value.HasValue;
        }
        public static bool IsDefined(object value)
        {
            return value != null;
        }
        public static bool IsDefined(JsonElement value)
        {
            return value.ValueKind != JsonValueKind.Undefined;
        }
        public static bool IsDefined(string value)
        {
            return value != null;
        }
    }
}