Tie::File lets you access each line of your file as an array element. It does not load the file into a multidimensional array. The reason for the warning is that you are trying to access an element in an Array-of-Arrays data structure, but you just have a simple array (perldsc). Maybe split will help: 
use warnings;
use strict;

my @file_array = qw(a|b|c d|e|f);
foreach my $row (0 .. @file_array - 1) {
    foreach my $column (split /\|/, $file_array[$row]) {
        print "$row $column\n";
    }
}

__END__

0 a
0 b
0 c
1 d
1 e
1 f

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In reply to Re^3: load a file in memory and extract parts by toolic
in thread load a file in memory and extract parts by healingtao

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