static IAsyncEnumerator <T> Create <T>(Func <CancellationToken, TaskCompletionSource <bool>, Task <bool> > moveNext, Func <T> current, Action dispose)
{
var self = default(IAsyncEnumerator <T>);
self = new AnonymousAsyncEnumerator <T>(
ct =>
{
var tcs = new TaskCompletionSource <bool>();
var stop = new Action(() =>
{
self.Dispose();
tcs.TrySetCanceled();
});
var ctr = ct.Register(stop);
var res = moveNext(ct, tcs).Finally(ctr.Dispose);
return(res);
},
current,
dispose
);
return(self);
}
private static IAsyncEnumerator <T> CreateEnumerator <T>(Func <CancellationToken, TaskCompletionSource <bool>, Task <bool> > moveNext, Func <T> current, Action dispose)
{
var self = default(IAsyncEnumerator <T>);
self = new AnonymousAsyncEnumerator <T>(
async ct =>
{
var tcs = new TaskCompletionSource <bool>();
var stop = new Action(
() =>
{
self.Dispose();
tcs.TrySetCanceled();
});
using (ct.Register(stop))
{
return(await moveNext(ct, tcs)
.ConfigureAwait(false));
}
},
current,
dispose
);
return(self);
}
