[UA-EAI] A radical idea for compatibility

[Paul Borokhov]

> 12 Dec 2017, в 17:47, John R. Levine <johnl at iecc.com> написал(а):
> 
>> Question: Is there any reason that clients should *not* punycode *all* addresses when sending messages and convert them back to proper Unicode at display time?
> 
> Yes.
> 
> For one thing, it would break mail to the majority of mail users who use ASCII mail clients.

Would it break them any worse than keeping the addresses in Unicode? In practice I have only seen places that choke on Unicode but go through fine with punycode, not the opposite.

> For another, the local parts of mail addresses are not always convertible to punycode,

Can you elaborate?

> or if they are, there is a non-reversible canonicalization step so if you undo the punycode, you'll end up with the wrong local part and it won't be deliverable.
> 
> R's.
> John
> 
> PS: It probably isn't a big surprise that this isn't the first time this suggestion has come up.