[syslog-ng] Quoting in filters

What is the policy on quoting values in filters? In the docs it seems that sometimes they are quoted and other times they are not. For example, are these equivalent: netmask (127.0.0.1/32) and netmask("127.0.0.1/32") I think that maybe some filters, the ones that take strings essentially, are quoted, and not the ones that take numeric data. Is that correct? Thanks, -Mark