public IArrayCache <TElement, TArrayKey> GetArrayCache <TArrayKey>(Func <TArrayKey, IObservable <TElement> > arrayRetriever)
{
return(new ArrayCache <TElement, TId, TArrayKey>(arrayRetriever,
_idExtractor,
e => _elementCache.Set(_idExtractor(e), e),
e => ElementCache.Get(e))
{
MaxAge = () => _arrayMaxAge ?? TimeSpan.FromMinutes(1)
});
}