public static Fabric.IAsyncEnumerable <TResult> SelectAsync <TSource, TResult>(this Fabric.IAsyncEnumerable <TSource> source, Func <TSource, Task <TResult> > selector)
{
if (source == null)
{
throw new ArgumentNullException(nameof(source));
}
if (selector == null)
{
throw new ArgumentNullException(nameof(selector));
}
return(Create(() =>
{
var e = source.GetEnumerator();
var current = default(TResult);
var cts = new CancellationTokenDisposable();
var d = Disposable.Create(cts, e);
return Create(async ct =>
{
if (await e.MoveNext(cts.Token).ConfigureAwait(false))
{
current = await selector(e.Current).ConfigureAwait(false);
return true;
}
return false;
},
() => current,
d.Dispose,
e
);
}));
}
public static Fabric.IAsyncEnumerable <TSource> WhereAsync <TSource>(this Fabric.IAsyncEnumerable <TSource> source, Func <TSource, int, Task <bool> > predicate)
{
if (source == null)
{
throw new ArgumentNullException(nameof(source));
}
if (predicate == null)
{
throw new ArgumentNullException(nameof(predicate));
}
return(Create(() =>
{
var e = source.GetEnumerator();
var index = 0;
var current = default(TSource);
var cts = new CancellationTokenDisposable();
var d = Disposable.Create(cts, e);
return Create(async ct =>
{
var b = false;
bool moveNext;
do
{
moveNext = await e.MoveNext(cts.Token).ConfigureAwait(false);
if (moveNext)
{
b = await predicate(e.Current, checked (index++)).ConfigureAwait(false);
}
} while (!b && moveNext);
if (b)
{
current = e.Current;
return true;
}
return false;
},
() => current,
d.Dispose,
e
);
}));
}
public static async Task ForEachAsyncAsync <TSource>(this Fabric.IAsyncEnumerable <TSource> source, Func <TSource, Task> action, CancellationToken cancellationToken)
{
if (source == null)
{
throw new ArgumentNullException(nameof(source));
}
if (action == null)
{
throw new ArgumentNullException(nameof(action));
}
using (var e = source.GetEnumerator())
{
while (await e.MoveNext(cancellationToken).ConfigureAwait(false))
{
await action(e.Current).ConfigureAwait(false);
}
}
}
public AsyncEnumerableFabricWrapper(Fabric.IAsyncEnumerable <T> inner)
{
_inner = inner;
}
public static IAsyncEnumerable <T> AsAsyncEnumerable <T>(this Fabric.IAsyncEnumerable <T> enumerable)
{
return(new AsyncEnumerableFabricWrapper <T>(enumerable));
}
public static Fabric.IAsyncEnumerable <TResult> SelectManyAsync <TSource, TResult>(this Fabric.IAsyncEnumerable <TSource> source, Func <TSource, int, Task <IAsyncEnumerable <TResult> > > selector)
{
if (source == null)
{
throw new ArgumentNullException(nameof(source));
}
if (selector == null)
{
throw new ArgumentNullException(nameof(selector));
}
return(Create(() =>
{
var e = source.GetEnumerator();
var ie = default(Fabric.IAsyncEnumerator <TResult>);
var innerDisposable = new AssignableDisposable();
var index = 0;
var cts = new CancellationTokenDisposable();
var d = Disposable.Create(cts, innerDisposable, e);
// ReSharper disable once RedundantAssignment
var inner = default(Func <CancellationToken, Task <bool> >);
var outer = default(Func <CancellationToken, Task <bool> >);
inner = async ct =>
{
if (await e.MoveNext(ct).ConfigureAwait(false))
{
return true;
}
innerDisposable.Disposable = null;
// ReSharper disable once AccessToModifiedClosure
// ReSharper disable once PossibleNullReferenceException
return await outer(ct).ConfigureAwait(false);
};
outer = async ct =>
{
if (await e.MoveNext(ct).ConfigureAwait(false))
{
var enumerable = await selector(e.Current, checked (index++)).ConfigureAwait(false);
ie = enumerable.GetEnumerator();
innerDisposable.Disposable = ie;
return await inner(ct).ConfigureAwait(false);
}
return false;
};
return Create(ct => ie == null ? outer(ct) : inner(ct),
() => ie.Current,
d.Dispose,
e
);
}));
}
