[Mailman-Developers] Regexp filtering

[Adam McGreggor]

On Tue, Mar 01, 2016 at 11:13:18PM +0900, Stephen J. Turnbull wrote:
> Adam McGreggor writes:
> 
>  > Or could we meet user expectations (real users, not geeks), [and
>  > allow glob syntax].
> 
> Definitely worth discussing, but my initial reaction is negative for
> the reasons discussed below.
> 
>  > Simples:
>  >     *@mail.ru
>  >     *@*mail.ru
>  >     ?????@mail.ru
> 
> Are those anchored?  At the beginning of string?  At end?  

'throughout'.


> Is there really a use case for "?"?  I don't see this as an obvious feature.

I'd imagine there could be some use for people wanting say, to handle
five-character localparts of an address, although it's an in-elegant
approach, it's something a user can understand, without needing to
understand regexp ("all our new subscriptions are five characters
before the @ sign. I want to block them").

> Globs are also too blunt for the use case, especially since bad actors
> do deliberately use fine distinctions between well-known domains and
> their own sinkholes of depravity when phishing. 

True. (I was picking on mail.ru, as it's one of the common ones that I
find quite irresponsible).

> Users are likely to
> be lazy, using "*@*mail.ru" to catch both "badactor at mail.ru" and
> "badactor at spamsource.mail.ru", trashing "niceguy at goodmail.ru"'s posts
> in the process.

Are they going to use *@* necessarily, or just *@? (unless they want
subdomains when "*@*.mail.ru" might be acceptable).

> 
>  > Off the top of my head, the syntax would define if it's an absolute
>  > address (foo at example.com) vs a regexp.
> 
> "foo at example.com" is unambiguous, but "foo+mailman at example.com" is
> not.  That's a big trap for users, who surely know exactly what they
> mean by that (and it's not foooooooooooomailman at example.com!)

Agree.

-- 
"applying logic to English slang is never a sound idea"
    -- Stephen Fry