Thanks for answers ;)

And later I've found a trivial "upgrade" to the initial range, for which I was blind yesterday... Just to add "int" in one place: 
push @array, reverse @array[ 0 .. int( $n / 2 ) - 1 ];

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In reply to Re: [SOLVED]: Need help with range expression ('0 .. -0.5' === '0 .. 0.5') by rsFalse
in thread [SOLVED]: Need help with range expression ('0 .. -0.5' === '0 .. 0.5') by rsFalse

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