// Needed for NET40
#if !NET_4_6
using System;

namespace LinqInternal.Threading.Needles
{
    internal interface IPromise
    {
        Exception Exception { get; }

        bool IsCanceled { get; }

        bool IsCompleted { get; }

        bool IsFaulted { get; }
    }

#if NETCF

    internal interface IPromise<T> : IPromise, IReadOnlyNeedle<T>
#else

    internal interface IPromise<out T> : IPromise, IReadOnlyNeedle<T>
#endif
    {
        // Empty
    }

    internal interface IWaitablePromise : IPromise
    {
        void Wait();
    }

#if NETCF

    public interface IWaitablePromise<T> : IPromise<T>, IWaitablePromise
#else

    internal interface IWaitablePromise<out T> : IPromise<T>, IWaitablePromise
#endif
    {
        // Empty
    }
}
#endif