/// <summary>
/// Remaps all the wildcards in an operation to unique identifiers.
/// </summary>
/// <param name="operation">The operation.</param>
/// <returns>The wrapped operation.</returns>
public static ReifiedOperation LiftWildcards(this ReifiedOperation operation)
{
if (operation == null)
{
throw new ArgumentNullException(nameof(operation));
}
return(LiftWildcards(operation, WildcardGenerator.Instance));
}
/// <summary>
/// Repeat an operation until cancellation is requested.
/// </summary>
/// <param name="operation">The operation.</param>
/// <param name="token">The cancellation token.</param>
/// <returns>The wrapped operation.</returns>
public static ReifiedOperation RepeatUntil(this ReifiedOperation operation, CancellationToken token)
{
if (operation == null)
{
throw new ArgumentNullException(nameof(operation));
}
return(new RepeatUntil(operation, token));
}
internal Repeat(ReifiedOperation operation, long count)
: base(ReifiedOperationKind.Repeat, operation)
{
if (count <= 0)
{
throw new ArgumentOutOfRangeException(nameof(count), "Count must be at least 0.");
}
Count = count;
}
/// <summary>
/// Starts an operation on a thread pool thread.
/// </summary>
/// <param name="operation">The operation.</param>
/// <param name="onStart">
/// A callback to return the task after the operation has been started.
/// </param>
/// <param name="token">
/// A cancellation token to give to the task factory.
/// </param>
/// <returns>The wrapped operation.</returns>
public static ReifiedOperation Async(this ReifiedOperation operation, Action <Task> onStart, CancellationToken token)
{
if (operation == null)
{
throw new ArgumentNullException(nameof(operation));
}
if (onStart == null)
{
throw new ArgumentNullException(nameof(onStart));
}
return(new Async(operation, onStart, token));
}
/// <summary>
/// Repeat an operation a given number of times.
/// </summary>
/// <param name="operation">The operation.</param>
/// <param name="count">The number of times to repeat the operation.</param>
/// <returns>The wrapped operation.</returns>
public static ReifiedOperation Repeat(this ReifiedOperation operation, long count)
{
if (operation == null)
{
throw new ArgumentNullException(nameof(operation));
}
if (count <= 0)
{
throw new ArgumentOutOfRangeException(nameof(count), "Count must be at least 0.");
}
return(new Repeat(operation, count));
}
/// <summary>
/// Remaps all the wildcards in an operation to identifiers taken from the wildcard generator.
/// </summary>
/// <param name="operation">The operation.</param>
/// <param name="generator">The wildcard generator.</param>
/// <returns>The wrapped operation.</returns>
public static ReifiedOperation LiftWildcards(this ReifiedOperation operation, IWildcardGenerator generator)
{
if (operation == null)
{
throw new ArgumentNullException(nameof(operation));
}
if (generator == null)
{
throw new ArgumentNullException(nameof(generator));
}
return(new LiftWildcards(operation, generator));
}
/// <summary>
/// Wraps a sequence of operations as a single, ordered operation.
/// </summary>
/// <param name="first">The first operation.</param>
/// <param name="rest">The rest of the operations.</param>
/// <returns>The wrapped operation.</returns>
public static ReifiedOperation Chain(this ReifiedOperation first, params ReifiedOperation[] rest)
{
if (first == null)
{
throw new ArgumentNullException(nameof(first));
}
if (rest == null)
{
throw new ArgumentNullException(nameof(rest));
}
return(new Chain(first, rest));
}
/// <summary>
/// Catches any exception thrown by the given operation.
/// </summary>
/// <param name="operation">The operation.</param>
/// <param name="handler">The callback for any exceptions thrown.</param>
/// <returns>The wrapped operation.</returns>
public static ReifiedOperation Catch(this ReifiedOperation operation, Action <Exception> handler)
{
if (operation == null)
{
throw new ArgumentNullException(nameof(operation));
}
if (handler == null)
{
throw new ArgumentNullException(nameof(handler));
}
return(new Catch <Exception>(operation, handler));
}
/// <summary>
/// Instruments an operation with callbacks that are invoked before and after the operation.
/// </summary>
/// <param name="operation">The operation.</param>
/// <param name="onEnter">
/// Callback to invoke prior to evaluating the operation.
/// </param>
/// <param name="onExit">
/// Callback to invoke after evaluating the operation.
/// </param>
/// <returns>The wrapped operation.</returns>
public static ReifiedOperation Instrument(this ReifiedOperation operation, Action onEnter, Action onExit)
{
if (operation == null)
{
throw new ArgumentNullException(nameof(operation));
}
if (onEnter == null)
{
throw new ArgumentNullException(nameof(onEnter));
}
if (onExit == null)
{
throw new ArgumentNullException(nameof(onExit));
}
return(new Instrument(operation, onEnter, onExit));
}
internal Chain(ReifiedOperation first, IEnumerable <ReifiedOperation> rest)
: base(ReifiedOperationKind.Chain, first)
{
if (rest == null)
{
throw new ArgumentNullException(nameof(rest));
}
else if (rest.FirstOrDefault() == null)
{
throw new ArgumentException("Expected at least one operation in the chain.", nameof(rest));
}
else if (rest.Any(o => o == null))
{
throw new ArgumentException("Chained operations must not be null.", nameof(rest));
}
Rest = rest;
}
/// <summary>
/// Binds a reified operation to a given environment.
/// </summary>
/// <typeparam name="TEnvironment">The environment type.</typeparam>
/// <param name="operation">The operation to bind.</param>
/// <param name="binder">The binder to use.</param>
/// <returns>
/// A lambda expression to evaluate the reified operation.
/// </returns>
public static Expression <Action <TEnvironment> > Bind <TEnvironment>(this ReifiedOperation operation, IReificationBinder <TEnvironment> binder)
{
if (operation == null)
{
throw new ArgumentNullException(nameof(operation));
}
if (binder == null)
{
throw new ArgumentNullException(nameof(binder));
}
var flattener = new ReifiedOperationFlattener();
var opBinder = new ReifiedOperationBinder <TEnvironment>(binder);
var flattened = flattener.Visit(operation);
var bound = opBinder.Visit(flattened);
return(binder.Optimize(bound));
}
/// <summary>
/// Visits a reified operation.
/// </summary>
/// <param name="operation">The operation.</param>
/// <returns>The result of visiting the operation.</returns>
public virtual TResult Visit(ReifiedOperation operation)
{
if (operation == null)
{
throw new ArgumentNullException(nameof(operation));
}
return(operation.Kind switch
{
ReifiedOperationKind.Async => VisitAsync((Async)operation),
ReifiedOperationKind.Catch => VisitCatch(operation),
ReifiedOperationKind.Chain => VisitChain((Chain)operation),
ReifiedOperationKind.Instrument => VisitInstrument((Instrument)operation),
ReifiedOperationKind.LiftWildcards => VisitLiftWildcards((LiftWildcards)operation),
ReifiedOperationKind.QueryEngineOperation => VisitQueryEngineOperation((QueryEngineOperation)operation),
ReifiedOperationKind.Repeat => VisitRepeat((Repeat)operation),
ReifiedOperationKind.RepeatUntil => VisitRepeatUntil((RepeatUntil)operation),
ReifiedOperationKind.ServiceOperation => VisitServiceOperation((ServiceOperation)operation),
_ => VisitExtension(operation),
});
protected override Expression <Action <TEnvironment> > VisitExtension(ReifiedOperation operation)
{
throw new NotImplementedException();
}
internal Async(ReifiedOperation operation, Action <Task> onStart, CancellationToken token)
: base(ReifiedOperationKind.Async, operation)
{
Token = token;
OnStart = onStart;
}
internal LiftWildcards(ReifiedOperation operation, IWildcardGenerator generator)
: base(ReifiedOperationKind.LiftWildcards, operation)
{
Generator = generator ?? throw new ArgumentNullException(nameof(generator));
}
internal RepeatUntil(ReifiedOperation operation, CancellationToken token)
: base(ReifiedOperationKind.RepeatUntil, operation)
{
Token = token;
}
internal OperationBase(ReifiedOperationKind kind, ReifiedOperation operation)
: base(kind)
{
Operation = operation ?? throw new ArgumentNullException(nameof(operation));
}
internal Catch(ReifiedOperation operation, Action <T> handler)
: base(ReifiedOperationKind.Catch, operation)
{
Handler = handler ?? throw new ArgumentNullException(nameof(handler));
}
internal Instrument(ReifiedOperation operation, Action onEnter, Action onExit)
: base(ReifiedOperationKind.Instrument, operation)
{
OnEnter = onEnter ?? throw new ArgumentNullException(nameof(onEnter));
OnExit = onExit ?? throw new ArgumentNullException(nameof(onExit));
}
