Having to know how many rows and columns there are in a multi-dimensioned array can become tedious. Unless strictly necessary you can avoid it having to code it into your program...

use strict;

sub dataSetup {
    return 
    (
                  [ qw|a b c d| ] , 
                  [ qw|a b c d| ] ,
                  [ qw|a b c d| ]
                  )
    ;         
}

sub main {
     my @multi = dataSetup();
                  
     foreach my $row (@multi){
          foreach(@$row){
               print qq|$_\n|;               
          }                   
     }
}
#----
&main;
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