public override Completion <TResult> Select <TResult>(Completion <T> result, Func <T, TResult> func) => interrupted <TResult>(exception);
public override bool ValueEqualTo(Completion <T> otherCompletion) => false;
public override Completion <T> Or(Completion <T> other) => other;
public override bool NotCompleted(out Completion <T> notCompleted) { notCompleted = this; return(true); }
public override bool IsCompleted(out Completion <T> completed) { completed = this; return(false); }
public override bool Else <TOther>(out Completion <TOther> result) { result = interrupted <TOther>(exception); return(true); }
public override Completion <TResult> Select <TResult>(Completion <T> result, Func <T, TResult> func) => cancelled <TResult>();
public override bool Else <TOther>(out Completion <TOther> result) { result = cancelled <TOther>(); return(true); }