FWIW it's possible in one statement but hardly "elegant" 
use strict;
use warnings;
use Data::Dump;

my %x = ( a  => "red");
my %y = ( b  => "green");
my %z = ( c  => "black");

sub assign {
   my (%x, %y, %z) = ( %{$_[0]}, %{$_[1]}, %{$_[2]} );
   dd  \(%x, %y, %z);
}

[download]

I'll post later a more elegant but significantly slower solution

UPDATE:
I was wrong, never mind. Thanks to Eily++

Cheers Rolf
(addicted to the Perl Programming Language and ☆☆☆☆ :)
Je suis Charlie!

In reply to Re: Elegantly dereferencing multiple references by LanX
in thread Elegantly dereferencing multiple references by Anonymous Monk

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