4 ms·
regex are proper code when written competently
by 1996 8y ago
regex are proper code when written competently
- bzbarsky 8y agoAssuming "competently" means "not using them when the grammar is not regular".
- mcny 8y agoI don’t even try. I put my hands up and accept [anything] @ [anything]
- Drdrdrq 8y agoWell, you can still check MX record for the second "anything", that should be pretty safe, right?
- ryanbrunner 8y agoI don't think that's sufficient on its own. If there's a CNAME on the domain, you'd have to follow the chain of CNAMEs to find an MX record (granted, that's not very common, but I think it's valid usage)
- JdeBP 8y agoResolving proxy DNS servers do that for you. A successful transaction against a resolving proxy DNS server yields a complete answer with all of the alias chain and the final resource record set (or "no such name" indicator). * http://jdebp.info./FGA/dns-query-resolution.html http://jdebp.info./FGA/dns-query-resolution.html
- wongarsu 8y agoAfter you removed the comments from the second anything, and checked that it isn't a raw IPv4 or IPv6 address. jsmith@[IPv6:2001:db8::1] is a valid email address, as is jsmith@(comment)example.com. Though you could argue that there are good reasons to disallow ip-based email addresses.
- Drdrdrq 8y agoThanks, didn't know that! E-mail is really full of surprises. :)