public T Single()
{
if (Rest.Any())
{
throw new Exception("Enumerable1 assumption for Single() failed - REST element was non-empty");
}
return(First);
}
public T Single()
{
if (Rest.Any())
{
throw new Exception("Array1 assumption for Single() failed - the length was actually " + Length);
}
return(First);
}
public bool Any(Func <T, bool> f) => f(First) || Rest.Any(f);
public T Last() => Rest.Any() ? Rest.Last() : First;
