use xor on the array indexes: 
my @foo = (1..8);

my @bar = @foo[map {$_ ^ 1} (0..$#foo)];

print "@bar";

[download]
Outputs 
2 1 4 3 6 5 8 7

[download]
- Miller

In reply to Re: Switch the odd/even elements of an array by wind
in thread Switch the odd/even elements of an array by jaredor

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