bug#51733: 27.1; Detect impossible email addresses better

[Lars Ingebrigtsen]

Lars Ingebrigtsen <larsi@gnus.org> writes:

> I think it looks like a fun little project -- it's so refreshing to have
> an actual spec to program against.  😸  And I've read most of the TS
> now, so it's just a small matter of typing.
>
> But I probably won't have the time this week -- if somebody else wants
> to get in on the action, please do go ahead.

Well, it took longer to find time to start this, but I think now's a
good time.

So we'll be importing a handful of new Unicode data files, and I think
an interface like

(suspicious-email-p "C𝗂𝗋𝖼𝗅𝖾@example.com")
=> "Confusables used in address: 𝗂 (MATHEMATICAL SANS-SERIF SMALL I) confusable 
with etc etc"

would be nice.  But there's also a bunch of lower level functions that
might be nice to expose separately, like

(single-script-p "Сirсlе")
=> nil

but it'd be nice to group these in a single package name.  But I'm
coming up blank.  I mean, `unicode-suspicious-email-p' would be
nonsensical, because ... it's not really Unicode that's the point here.
For instance, if you have a link text like http://innocent.org but the
link goes to http://evil.com, then it'd be nice to implement something
for that, too, in this same package.  Or http://paypaI.com, for that
matter.

So does anybody have an idea for a package name, so I can start typing
away at this?  😀

-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no