[whatwg] Comments on the definition of a valid e-mail address

[Aryeh Gregor]

On Sun, Aug 23, 2009 at 3:41 PM, Aryeh Gregor<Simetrical+w3c at gmail.com> wrote:
> Alternatively, you could just loosen the restrictions even further,
> and only ban input that doesn't contain an @ sign.  (Or that doesn't
> match ^[^@]+@[^@]+\.[^@]+$, or whatever.)  Or just don't ban anything
> at all, like with type=tel.  type=email differs from most of the other
> types with validity constraints (like month, number, etc.) in that the
> difference between valid and invalid values is a purely pragmatic
> question (what will actually work?) that the user can often answer
> better than the application.  It doesn't seem like a good idea for the
> standard to tell users that the e-mail addresses they've actually been
> using are invalid.

. . . and I should add that I think it might be useful to have an note
recommending that application authors not do any validation beyond
what the spec ends up mandating as required (preferably almost
nothing).  I've had a lot of problems with sites that think + isn't
valid in e-mail addresses, including pretty major sites that should
know better.  You don't really know if it will work anyway until you
try actually sending mail to it -- maybe the local part was mistyped
or invented -- so why not just do that?