0 vs 1-based index

[dclong]

n - The current 1-based line number.

This seems a little bit confusing as the field index is 0-based. I suggest make them consistent. It is probably better to use 0-base index as that's what Python does.

[alecthomas]

That's not going to change now as it would break existing usage. From memory I did that so as to be consistent with awk's NR.