While it can be done with a single loop, it seems to me you have to use less intuitive coding techniques to enforce that arbitrary constraint.

I'm beyond understanding why not just use a nested loop and be done with it. 

#!/usr/bin/perl -w

use strict;

foreach my $y_axis (1..8) {
    my $output_text = '';
    foreach my $x_axis (1..8) {
        $output_text .= " $x_axis$y_axis ";
    }
    print "$output_text\n";
}

exit;

__END__

C:\Steve\Dev\PerlMonks\P-2013-10-03@1652-8x8-Loop>8x8.pl
 11  21  31  41  51  61  71  81
 12  22  32  42  52  62  72  82
 13  23  33  43  53  63  73  83
 14  24  34  44  54  64  74  84
 15  25  35  45  55  65  75  85
 16  26  36  46  56  66  76  86
 17  27  37  47  57  67  77  87
 18  28  38  48  58  68  78  88

[download]

That said, BrowserUK produced, as usual, a brilliant one-loop solution.

In reply to Re: Chess Board Single Loop by marinersk
in thread Chess Board Single Loop by xantithor

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