sub flattened_json { 
        my ($cur_node, $top_path, $put_here) = @_; 

        $top_path //= []; 
        $put_here //= {}; 

        if (ref $cur_node eq "HASH") { 
                flattened_json($$cur_node{$_}, [ @$top_path, $_ ], $put_here)
                        for sort keys %$cur_node; 
        } elsif (ref $cur_node eq "ARRAY") { 
                flattened_json($$cur_node[$_], [ @$top_path, $_ ], $put_here) 
                        for 0 .. @$cur_node - 1; 
        } else { 
                $$put_here{
                        join " ➔ ", 
                        map { $json_do->pretty(0)->encode($_) =~ s/➔/➔➔/gr } 
                        @$top_path
                } = $json_do->pretty(0)->encode($cur_node) =~ s/➔/➔➔/gr; 
        } 

        return $put_here; 
}