Dear Lazyweb, please put me out of my misery.

I have a string that looks something like:

a b c foo {0 1 2} fred {3 4 5} {{5 4 3} {2 1 0}} quux

I want to output: 

a
b
c
foo
{0 1 2}
fred
{3 4 5}
{{5 4 3} {2 1 0}}
quux

(actually I want each line to be an array element, but that's obviously easy)

Can I do this with a Perl regex? Originally I thought I was going to have to walk the string like I would in C, but some playing around (and local help) got me to: 

my $match = qr/(?:\s*[^\{\}\s]+\s*|\{(?R)\})/;

while ($cur =~ m/($match)\s+(.*)/o) {
        print $1, "\n";
        $cur = $2;
}

which sort of gets me there, except I get

{0 1 2} fred {3 4 5} {{5 4 3} {2 1 0}}

as one line instead of 4.

What obvious thing am I missing here?