In split, it is explained that split; defaults to split ' ', $_;.

\@numbers is not de-referencing but is creating a reference to the array @numbers. So @matrix will be an array of array references. Without it, the push would push all individual elements of @numbers onto @matrix, effectively creating a long one-dimensional list instead of a matrix.

In reply to Re: Explaining small Code by hdb
in thread Explaining small Code by madM

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