/// <summary>
/// Returns a cloud computation that will execute the given computation on every available worker
/// possibly in parallel and will return when any of the supplied computations
/// have returned a successful value or if all of them fail to succeed.
/// If a computation succeeds the rest of them are canceled.
/// The success of a computation is encoded as an option type.
/// This operator may create distribution.
/// </summary>
/// <typeparam name="TResult">Computation return type.</typeparam>
/// <param name="workflow">Input workflow to be executed nondeterministically everywhere.</param>
/// <returns>The result of the first computation to complete in the positive.</returns>
public static Cloud <Option <TResult> > Choice <TResult>(Cloud <Option <TResult> > workflow)
{
Func <Option <TResult>, MBrace.Cloud <FSharpOption <TResult> > > transform = option => Builder.Return(option.AsFSharpOption());
var fsTransform = transform.AsFSharpFunc();
var x = Builder.Bind(workflow, fsTransform);
var choice = MCloud.Choice(x);
Func <FSharpOption <TResult>, MBrace.Cloud <Option <TResult> > > transformRev = fsOption => Builder.Return(Option <TResult> .FromFSharpOption(fsOption));
var fsTransformRev = transformRev.AsFSharpFunc();
var result = Builder.Bind(choice, fsTransformRev);
return(result);
}
/// <summary>
/// Performs a nondeterministic computation in parallel.
/// </summary>
/// <typeparam name="TResult">Computation return type.</typeparam>
/// <param name="workflows">Input workflows to be executed nondeterministically.</param>
/// <returns>The result of the first computation to complete in the positive.</returns>
public static Cloud <Option <TResult> > Choice <TResult>(this IEnumerable <Cloud <Option <TResult> > > workflows)
{
Func <Option <TResult>, MBrace.Cloud <FSharpOption <TResult> > > transform = option => Builder.Return(option.AsFSharpOption());
var fsTransform = transform.AsFSharpFunc();
var wfs = workflows
.Select(wf => Builder.Bind(wf, fsTransform))
.ToArray();
var choice = MCloud.Choice <TResult>(wfs);
Func <FSharpOption <TResult>, MBrace.Cloud <Option <TResult> > > transformRev = fsOption => Builder.Return(Option <TResult> .FromFSharpOption(fsOption));
var fsTransformRev = transformRev.AsFSharpFunc();
var result = Builder.Bind(choice, fsTransformRev);
return(result);
}