sub walk
{
	my( $v, @path ) = @_;
	foo( @path );
	if ( keys %$v )
	{
		for my $k ( sort keys %$v )
		{
			walk( $v->{$k}, @path, $k );
		}
	}
}

##</code><code>##

sub walk
{
	my( $v, @path ) = @_;
	foo( @path ) or return; # true means recurse
	if ( keys %$v )
	{
		for my $k ( sort keys %$v )
		{
			walk( $v->{$k}, @path, $k );
		}
	}
}

##</code><code>##

sub walk
{
	my( $cb, $v, @path ) = @_;
	$cb->( @path ) or return; # true means recurse
	if ( keys %$v )
	{
		for my $k ( sort keys %$v )
		{
			walk( $cb, $v->{$k}, @path, $k );
		}
	}
}