... I did not understand what the pipeline does ...

The  | (pipe) character merely serves as a visual demarcation in the code example to allow the result of the operations to be better seen. Same thing as
    $selected = $1 . " | " . $2 . " | " . $3 . " | " . $4. " | " . $5;
here.

In reply to Re^3: newbie need help with a simple code by AnomalousMonk
in thread newbie need help with a simple code by perlmonk007

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