Two solutions come to mind. Either grep as you mentioned: 
my $i = 0;
my @even = grep $i++ % 2, @array

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Or you can build a list containing even numbers and use it to take a slice from the array: 
my @idx = map $_ * 2, 0 .. $#array / 2;
my @even = @array[@idx];

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Here I make a list of consecutive numbers going from 0 to half the value of the biggest array index, then use map to multiply them all by two, giving me a list of all the even indices into the array. Of course you can get rid of the temporary array entirely: 
my @even = @array[map $_ * 2, 0 .. $#array / 2];

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Since both approaches loop - either over the array or over a list of indices -, I'd probably use the grep solution as it doesn't have to build an extra list, which can consume a lot of memory for large arrays. I showed the index list technique because it is also useful in other cases - f.ex, when you want to access the same elements of several arrays, it's usually the best approach.

Makeshifts last the longest.

In reply to Re: Array Parse by Aristotle
in thread Array Parse by Anonymous Monk

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