I can't believe you missed out on this opportunity to wave (--) the magic wand variable ($|) to get only the odd or even elements of a list: 
print grep --$|,($|||=1)&& /\b(\w+)\b(?=(.*?)\b\1\b)/g'

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In reply to Re: Re: Regex help by ysth
in thread Regex help by toonski

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