I've no idea why, but as with the first answer in this thread it seems to make $previous_line always be the first line in the file.

In reply to Re^6: How to loop over two lines, alter a value in the current line and save it to the previous line? by rjc33
in thread How to loop over two lines, alter a value in the current line and save it to the previous line? by rjc33

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