internal static bool TryUseExisting <T>(this IComputed <T>?existing, ComputeContext context, IComputed?usedBy)
{
var callOptions = context.CallOptions;
var useExisting = (callOptions & CallOptions.TryGetExisting) != 0;
if (existing == null)
{
return(useExisting);
}
if (!(useExisting || existing.IsConsistent()))
{
return(false);
}
context.TryCapture(existing);
var invalidate = (callOptions & CallOptions.Invalidate) == CallOptions.Invalidate;
if (invalidate)
{
existing.Invalidate();
return(true);
}
if (!useExisting)
{
((IComputedImpl?)usedBy)?.AddUsed((IComputedImpl)existing !);
}
((IComputedImpl?)existing)?.RenewTimeouts();
return(true);
}
internal static bool TryUseExisting <T>(this IComputed <T>?existing, ComputeContext context, IComputed?usedBy)
{
var callOptions = context.CallOptions;
var useExisting = (callOptions & CallOptions.TryGetExisting) != 0;
if (existing == null)
{
return(useExisting);
}
useExisting |= existing.IsConsistent();
if (!useExisting)
{
return(false);
}
if ((callOptions & CallOptions.Capture) != 0)
{
Interlocked.Exchange(ref context.CapturedComputed, existing);
}
if ((callOptions & CallOptions.Invalidate) == CallOptions.Invalidate)
{
existing.Invalidate();
return(true);
}
((IComputedImpl?)usedBy)?.AddUsed((IComputedImpl)existing !);
((IComputedImpl?)existing)?.RenewTimeouts();
return(true);
}
public static void Invalidate(this IComputed computed, TimeSpan delay, bool?usePreciseTimer = null)
{
if (delay <= TimeSpan.Zero)
{
computed.Invalidate();
return;
}
var bPrecise = usePreciseTimer ?? delay <= TimeSpan.FromSeconds(1);
if (!bPrecise)
{
Timeouts.Invalidate.AddOrUpdateToEarlier(computed, Timeouts.Clock.Now + delay);
computed.Invalidated += c => Timeouts.Invalidate.Remove(c);
return;
}
var cts = new CancellationTokenSource(delay);
computed.Invalidated += _ => {
try {
if (!cts.IsCancellationRequested)
{
cts.Cancel(true);
}
} catch {
// Intended: this method should never throw any exceptions
}
};
cts.Token.Register(() => {
// No need to schedule this via Task.Run, since this code is
// either invoked from Invalidate method (via Invalidated handler),
// so Invalidate() call will do nothing & return immediately,
// or it's invoked via one of timer threads, i.e. where it's
// totally fine to invoke Invalidate directly as well.
computed.Invalidate();
cts.Dispose();
});
}
