Am I correct if I assume that here $_ is defined as 'one single digit or maybe a few digits ...

No, $_ is array reference not a scalar. $_ is not being tested for simple number-ness, but the deferenced value, $_->[0], is. Other than that, you are correct in your reading about which value is eventually going to be added.

- parv

In reply to Re^3: Data::Table - empty values - avoid warnings by Anonymous Monk
in thread Data::Table - empty values - avoid warnings by GertMT

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