in reply to Re: How Perl can push array into array and then how retrieve
in thread How Perl can push array into array and then how retrieve

"Now that I think about it, $i+=2 ..."
I think OP was meaning to have step in Perl for loop.
  • Comment on Re^2: How Perl can push array into array and then how retrieve

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Re^3: How Perl can push array into array and then how retrieve
by choroba (Cardinal) on Nov 25, 2021 at 14:16 UTC
    There is more than one way to do it.

    You can compute calculate the numbers from a simple sequence: 

    my @f;
for my $i (0 .. 20) {
    my @e = (2 * $i, 2 * $i + 1);
    push @f, \@e;
}
print map "(@$_)", @f

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    or you can use the C-style loop to skip over the unwanted numbers: 
    for (my $i = 0; $i <= 40; $i += 2) {
    my @e = ($i, $i + 1);
    push @f, \@e;
}

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    or you can use grep to filter the numbers you want: 
    for my $i (grep 0 == $_ % 2, 0 .. 40) {
    my @e = ($i, $i + 1);
    push @f, \@e;
}

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    etc.

    map{substr$_->[0],$_->[1]||0,1}[\*||{},3],[[]],[ref qr-1,-,-1],[{}],[sub{}^*ARGV,3]
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Re^3: How Perl can push array into array and then how retrieve
by bliako (Abbot) on Nov 25, 2021 at 15:31 UTC

    here is another way to have a step in this kind of loop:

    for my $i (map { $_ * 2 } 0..40/2){
   ...
}

    [download]
[reply]
[d/l]

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