The wrong brackets here in => csv { and missing the closing one from csv (

Try this 

csv (
  in => csv ( # not {
    in             => *INPUT,
    blank_is_undef => 1,
    on_in          => sub { $_ //= "NULL" for @{$_[1]}; },
  ),
  out => *OUTPUT,
  eol => $/,
);

[download]
poj

In reply to Re^6: insert null in missing places of csv by poj
in thread insert null in missing places of csv by ukhare

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