It will be interesting to see how this fares in a benchmark.

 
#! perl -slw 
use strict; 
use List::Util qw[ reduce ]; 
sub topN{ 
    my( $n, $aref ) = @_; 
    my @topN; 
    push @topN, reduce{ 
        $a > $b && ( !@topN || $a < $topN[ -1 ] ) 
            ? $a : ( !@topN || $b < $topN[ -1 ] ) 
            ? $b : $a; 
    } @$aref for 1 .. $n; 
    return @topN; 
} 
my @test = 1 .. 100; 
print join ', ', topN 5, \@test;
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