$_ = "'foo',123,'bar\\'cuz', 'comma,comma',,'void'";
while(/('(.*?)'|([^']*?))($|,\s*)/g)
{
        my $t = $2 || $3;
        print ">$t\n";
}
___________
>foo
>123
>bar\'cuz
>comma,comma
>
>void
>

##</code><code>##

$_ = "'foo',123,'bar\\'cuz', 'comma,comma',,'void'";

map { my $t = $2 || $3; print "<$t\n"; } 
  m/('(.*?)'|([^']*?))($|,\s*)/g;

______________
<'foo'
<foo
<
<,
<123
<
<123
<,
<'bar\'cuz'
<bar\'cuz
<
<,
<'comma,comma'
<comma,comma
<
<,
<
<
<
<,
<'void'
<void
<
<
<
<
<
<