in reply to Unobvious Pathological Code Snippets

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.

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Re^2: Unobvious Pathological Code Snippets
by QM (Parson) on Mar 28, 2006 at 18:52 UTC
    <Tim "The Toolman" Taylor>

    Hrruuhhhh???

    </Tim "The Toolman" Taylor>

    While that's devilish and all that, how is it pathological? Heck, it doesn't even DWIM unless $n divides @_.

    The interesting bit, to me, is passing arguments to the anonymous sub.

    I guess I should have stated more explicitly that I'm looking for things that can't be grokked without deep diving into the docs or the source code. For instance, the continue/next behavior is documented, rather humorously, as "entertaining", without being so explicit as to spoil the fun.

    -QM
    --
    Quantum Mechanics: The dreams stuff is made of

[reply]
[d/l]
[select]

      The thing to note is that despite having "destructively" spliced the array into chunks, the array remains unchanged after the process.

      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.
[reply]
        Oh, OK. I wasn't expecting this, but it's within the parameters, Jim ;)

        Is it then a copy instead of the original?

        So what are the critical characteristics? Is it the anonymous sub? The map? Or the whole gestalt? (And is "whole gestalt" pleonastic?)

        -QM
        --
        Quantum Mechanics: The dreams stuff is made of

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