Re: alternate array elements

Another way to do it:

$ perl -le'
use List::MoreUtils "natatime";
my @x = "a" .. "z";
my $iter = natatime 2, @x;
my @even;
while ( my @y = $iter->() ) {
    push @even, $y[ 0 ];
    }
print "@even";
'
a c e g i k m o q s u w y
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Re^2: alternate array elements by Anonymous Monk on May 20, 2010 at 15:14 UTC
Thanks all! toolic I didn't know of supersearch so that's useful cdarke I like the keys approach, hadn't thought of that at all and presumably it's fast, will try that next time if I don't need to preserve order. For posterity, I decided I actually needed the ODD indices (fwiw, the array has duplicate values in it and I'm porting VBA code which uses 1-based arrays, hence want to keep $all[0] as it = undef) so I used: `@odd = @all[grep($_%2==0, 0..$#all)];` or seomething like that. I guess the not would be faster tho, but I think it'd confuse my readers more, they'll already be struggling with grep, % and $#!!	[reply] [d/l]
Re^3: alternate array elements by Anonymous Monk on May 20, 2010 at 15:17 UTC
gah should have said evens - basically edited solution by almac at the top now	[reply]