Prototype of gRPC C# library (Core and API examples)
diff --git a/src/csharp/GrpcApi/DummyMathServiceClient.cs b/src/csharp/GrpcApi/DummyMathServiceClient.cs
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+using System;
+using System.Threading;
+using System.Threading.Tasks;
+using System.Collections.Generic;
+using System.Reactive.Linq;
+
+namespace math
+{
+// /// <summary>
+// /// Dummy local implementation of math service.
+// /// </summary>
+// public class DummyMathServiceClient : IMathServiceClient
+// {
+// public DivReply Div(DivArgs args, CancellationToken token = default(CancellationToken))
+// {
+// // TODO: cancellation...
+// return DivInternal(args);
+// }
+//
+// public Task<DivReply> DivAsync(DivArgs args, CancellationToken token = default(CancellationToken))
+// {
+// return Task.Factory.StartNew(() => DivInternal(args), token);
+// }
+//
+// public IObservable<Num> Fib(FibArgs args, CancellationToken token = default(CancellationToken))
+// {
+// if (args.Limit > 0)
+// {
+// // TODO: cancellation
+// return FibInternal(args.Limit).ToObservable();
+// }
+//
+// throw new NotImplementedException("Not implemented yet");
+// }
+//
+// public Task<Num> Sum(IObservable<Num> inputs, CancellationToken token = default(CancellationToken))
+// {
+// // TODO: implement
+// inputs = null;
+// return Task.Factory.StartNew(() => Num.CreateBuilder().Build(), token);
+// }
+//
+// public IObservable<DivReply> DivMany(IObservable<DivArgs> inputs, CancellationToken token = default(CancellationToken))
+// {
+// // TODO: implement
+// inputs = null;
+// return new List<DivReply> { }.ToObservable ();
+// }
+//
+//
+// DivReply DivInternal(DivArgs args)
+// {
+// long quotient = args.Dividend / args.Divisor;
+// long remainder = args.Dividend % args.Divisor;
+// return new DivReply.Builder{ Quotient = quotient, Remainder = remainder }.Build();
+// }
+//
+// IEnumerable<Num> FibInternal(long n)
+// {
+// long a = 0;
+// yield return new Num.Builder{Num_=a}.Build();
+//
+// long b = 1;
+// for (long i = 0; i < n - 1; i++)
+// {
+// long temp = a;
+// a = b;
+// b = temp + b;
+// yield return new Num.Builder{Num_=a}.Build();
+// }
+// }
+// }
+}
+