Another way: 

my @x = (1, 22, 3, -4 );
print join " ", grep { state $i; $i++ % 2 == 0 } reverse @x;

[download]

The documentation advises against using map purely for its side effects. If you're not going to use the resulting list, use a for loop instead, or in the case of simply filtering a list down to a smaller list, grep.

As far as performant, I don't think you can tell much about the performance of the loop when you are opening and closing a file and only processing one line with four elements: the I/O will eat up most of the time no matter the solution.

Hope this helps!

update: show with grep


The way forward always starts with a minimal test.

In reply to Re: printing every 2nd entry in a list backwards by 1nickt
in thread printing every 2nd entry in a list backwards by Anonymous Monk

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