namespace System.Reactive.Linq.ObservableImpl { internal abstract class CombineLatestSink<TResult> : IdentitySink<TResult>, ICombineLatest { protected readonly object _gate; private bool _hasValueAll; private readonly bool[] _hasValue; private readonly bool[] _isDone; protected CombineLatestSink(int arity, IObserver<TResult> observer) : base(observer) { _gate = new object(); _hasValue = new bool[arity]; _isDone = new bool[arity]; } public void Next(int index) { if (!_hasValueAll) { _hasValue[index] = true; bool hasValueAll = true; bool[] hasValue = _hasValue; for (int i = 0; i < hasValue.Length; i++) { if (!hasValue[i]) { hasValueAll = false; break; } } _hasValueAll = hasValueAll; } if (_hasValueAll) { TResult val = default(TResult); try { val = GetResult(); } catch (Exception error) { ForwardOnError(error); return; } ForwardOnNext(val); } else { bool flag = true; for (int j = 0; j < _isDone.Length; j++) { if (j != index && !_isDone[j]) { flag = false; break; } } if (flag) ForwardOnCompleted(); } } protected abstract TResult GetResult(); public void Fail(Exception error) { ForwardOnError(error); } public void Done(int index) { _isDone[index] = true; bool flag = true; bool[] isDone = _isDone; for (int i = 0; i < isDone.Length; i++) { if (!isDone[i]) { flag = false; break; } } if (flag) ForwardOnCompleted(); } } }