This, (attributable to Juerd) is kinda cute, and a little surprising: 

my @a = '01' .. '30';
print "@$_" for sub{
    my $n=shift; 
    map{ [ splice @_, 0, $n ] } 0 .. @_ / $n 
}->( 5, @a );

01 02 03 04 05
06 07 08 09 10
11 12 13 14 15
16 17 18 19 20
21 22 23 24 25
26 27 28 29 30

print @a;
01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17 18 19 20 21 22 23 2
+4 25 26 27 28 29 30

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Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
Lingua non convalesco, consenesco et abolesco. -- Rule 1 has a caveat! -- Who broke the cabal?
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.

In reply to Re: Unobvious Pathological Code Snippets by BrowserUk
in thread Unobvious Pathological Code Snippets by QM

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