It seems like you got everything. Except I want to make sure you realize that $. is the number of lines (or more precisely "the number of records") you've read from your input file, not the line number of the program. So if you're thinking that it equals 3 because it's the third line of your program, that's not right. If you're not reading from any input files, it should be 0.

(Though I do note that $. increases as I use the debugger...)

Update: Actually it seems to be undef when I try it before reading input lines, not 0.

buckaduck