in reply to Transpose a file

One-liner: 
perl  -na -E "BEGIN{$c=0};
               $x[$_][$c]=$F[$_] for 0..$#F;
               $c++}
             {say qq|@$_| for @x" transpose-this.txt

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        This is not an optical illusion, it just looks like one.

Replies are listed 'Best First'.
Re^2: Transpose a file
by Discipulus (Canon) on May 11, 2016 at 08:24 UTC
    OK and ++NetWallah but now you explain this to me: at first glance i saw the BEGIN and seemed to me not necessary, but after a while I saw $c++}  { part and i said: this is a typo.. but no! it compiles and run fine as all code you post.

    Removing the BEGIN block.. 

    perl  -na -E "$x[$_][$c||0]=$F[$_] for 0..$#F; $c++} {say qq|@$_| for 
+@x"

    [download]

    ..deparsed becomes: 

    BEGIN {
    $^H{'feature_unicode'} = q(1);
    $^H{'feature_say'} = q(1);
    $^H{'feature_state'} = q(1);
    $^H{'feature_switch'} = q(1);
}
LINE: while (defined($_ = <ARGV>)) {
    our(@F) = split(' ', $_, 0);
    $x[$_][$c or 0] = $F[$_] foreach (0 .. $#F);
    ++$c;
}
{
    say "@$_" foreach (@x);
}

    [download]

    So your evil trick ;=) to use } { is to break the implicit loop created by -n ? and doing so you have a fictional END block?

    If so, I prefere (in this case) readabilty over magic:

    perl -na -E "$x[$_][$c||0]=$F[$_] for 0..$#F; $c++; END{say qq|@$_| for @x}"

    L*

    There are no rules, there are no thumbs..
    Reinvent the wheel, then learn The Wheel; may be one day you reinvent one of THE WHEELS.
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[d/l]
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      > evil trick

      See "Eskimo greeting" in perlsecret.

      ($q=q:Sq=~/;[c](.)(.)/;chr(-||-|5+lengthSq)`"S|oS2"`map{chr |+ord
}map{substrSq`S_+|`|}3E|-|`7**2-3:)=~y+S|`+$1,++print+eval$q,q,a,

      [download]
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[d/l]
        noo there is something here around called perlsecret and nobody told me?!

        thanks choroba i'll open the link next christmas.. ;=)

        L*

        There are no rules, there are no thumbs..
        Reinvent the wheel, then learn The Wheel; may be one day you reinvent one of THE WHEELS.
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[d/l]
[select]
      Thanks for the de-parse (++). I will agree with you on the readability of the END block vs Eskimo greeting.

      In the same spirit, I think the $c=0 initialization in the BEGIN block is clearer than [$c||0].

              This is not an optical illusion, it just looks like one.

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