Re: [PATCH v3] Allow applying filters to summary consecutively

[Gregory Heytings]

> > Yes, my point was to mention the two less mathematical words: 
> > broadening and narrowing.
>
> Narrowing is already being used, but it needs explanation, being a 
> general notion.  I was looking for a single word or max 2 words,

This subtread is about rmail-summary-apply-filters-consecutively, right? 
Here's an attempt to make it clearer:

If non-nil, apply Rmail summary commands on the already existing 
filtering.

When this variable is non-nil, `rmail-summary-by-*' commands work on the 
already existing summary, if any.  This allows gradual narrowing of the 
selection of messages, that is, each `rmail-summary-by-*' command 
restricts the selection of messages further.

When this variable is nil, each `rmail-summary-by-*' command is applied 
anew on the entire mailbox.

> > That being said, I don't user Rmail but I don't think it obvious that 
> > filtering is always "intersection".  Someone may filter their inbox to 
> > see mails from Alice, and add mails from Alice to the filtering.
>
> You could read about it in the manual.  It doesn't make a lot of sense 
> to suggest terminology for features you are not familiar with.

Well, the fact that I don't use Rmail doesn't mean that I'm not familiar 
with that feature, which exists in other MUAs.