I guess you are using | as a separator. The problem with your approach is that you want to replace the content, but you are matching the separators as well - but separators are "shared". One way of solving this is the use of split and join: 
join "|" => map {length () ? $_ : '\N'} split /[|]/ => $line, -1;

[download]
But that assumes there are no leading or trailing vertical bars. Or you can use lookahead: 
$line =~ s'[|](?=[|])'|\N'g;

[download]

Abigail

In reply to Re: Broken regexp by Abigail-II
in thread Broken regexp by ColtsFoot

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