#!/usr/bin/perl
use Data::Dumper;

$var = [
            { x => 1 },
            { y => 2 },
            { z => 3 }
          ];


my %res;
foreach my $v (@{$var}) {
     my ($k) = keys %$v;
     $res{$k} = $v->{$k};
}
print Dumper \%res;