5
This comment led me to RFC 5322 § 3.4.1 which reads:
An addr-spec is a specific Internet identifier that contains a locally
interpreted string followed by the at-sign character ("@", ASCII value
64) followed by an Internet domain.
The locally interpreted string is either a quoted-string or a dot-atom.
If the string can be represented as a dot-atom (that is, it contains no
characters other than atext characters or "." surrounded by atext
characters), then the dot-atom form SHOULD be used and the quoted-
string form SHOULD NOT be used. Comments and folding white space
SHOULD NOT be used around the "@" in the addr-spec.
And we can see what atext
is here.
atext = ALPHA / DIGIT / ; Any character except controls,
"!" / "#" / ; SP, and specials.
"$" / "%" / ; Used for atoms
"&" / "'" /
"*" / "+" /
"-" / "/" /
"=" / "?" /
"^" / "_" /
"`" / "{" /
"|" / "}" /
"~"
Putting this all together, does that mean that the email address email@"happy@guy.com"
is actually a valid address, since the quotes allow the usage of the @
symbol?
Interesting. Letters, digits, and hyphens are all
atext
. So I wonder what kind of domain would require quotes as specified in 3.4.1? – Cory Klein – 2013-09-26T19:44:30.133Ah, I think I have been reading it incorrectly. When mentioning the quotes it is talking about the text before the
@
sign and domain. So maybe "email@email"@happyguy.com is a valid email address? – Cory Klein – 2013-09-26T19:45:43.1701From RFC 5322 regarding the domain name: "Note: A liberal syntax for the domain portion of addr-spec is given here. However, the domain portion contains addressing information specified by and used in other protocols (e.g., [RFC1034], [RFC1035], [RFC1123], [RFC5321]). It is therefore incumbent upon implementations to conform to the syntax of addresses for the context in which they are used." – Ƭᴇcʜιᴇ007 – 2013-09-26T19:52:10.993
1
in general Wikipedia's descriptions are a little less cryptic than the RFC's. Check out http://en.wikipedia.org/wiki/E-mail_address#Local_part
– Ƭᴇcʜιᴇ007 – 2013-09-26T20:00:03.950You could use
"H@ppy_guy"@domain.tld
as mail address, or"Happy@guy..demo"@domain.tld
. It would be legal but many websites would break on it. Most do not even accept other legal uses such asmy_name+spam_from_blah@domain.tld
. I think they would also break on the other examples. – Hennes – 2013-09-26T20:04:53.210@Hennes On the bright side, that would probably also break many spambots... – Tobias Kienzler – 2013-09-27T10:39:22.670
Yup. That us why I use it. In the past my mail averaged 10 real mail per day, and 131 spams per day (Spam filtering turned off for a month in order to gather statistics). So I used "mynane+thiswebsiteused@mydomain.tld". Sadly that does not work with some websites which are made by amateurs, such as VISA and VMware. (Worse, it used to work with vmware, they later 'improved' the site preventing my from logging in or resetting my password). – Hennes – 2013-09-27T13:13:23.320
2Sometimes you can work around this because the email address input mis-validator is on the actual webpage and then you can use things like firebug or webscarab to edit the script which incorrectly validates stuff. It is annoying though. – Hennes – 2013-09-27T13:14:21.030