For a while, R has been generating a warning for if (x) when length(x)
1. With length(x) == 0, we get an error.
x <- logical(0) if (x) 1;
Error in if (x) 1 : argument is of length zero
x <- logical(1) if (x) 1; x <- logical(2) if (x) 1;
Warning message: In if (x) 1 : the condition has length > 1 and only the first element will be used Time to make the length(x) > 1 case an error to? Is there any sane programming reason why it should work as if (x[1]) with a warning? How many bugs propagate because of this? /Henrik