Verify an e-mail-adress - syntax and dns

[Christophe]

Georg Brandl a écrit :
> Christophe wrote:
>> Steven D'Aprano a écrit :
>>> By memory, in an thread about the same topic just a few days ago, 
>>> Fredrik
>>> Lundh posted a link to Perl's FAQs that suggests a method for 
>>> "validating"
>>> email addresses: treat it like a password and ask the user to type it
>>> twice. That will protect against simple typos and input errors.
>>
>> I hate that thing. When I see that, I type my email once and 
>> copy/paste into the second edit box. This is useless AND annoying at 
>> the same time.
> 
> It may be for you, but there certainly are users that misspel their
> e-mail address more frequently, just like passwords. And therefore it's a
> nice touch to spare both the original submitter and the owner of the
> misspelled address more work.

Which proportion of the people that sometimes misspell their e-mail also 
use cut&paste when faced with "please type your e-mail twice" web pages?