Hi, I posted this in the help forum and a mod confirmed it is not currently available:
I'd like wp to provide a way to create a feed with multiple categories, where all must be true, as opposed to any.
I know you can do ?cat=1,2,3,etc. to get all posts in any one of those categories, but I want a feed of posts that are categorized as all three. I tried ?cat=1+2+3+etc. similar to how you combine terms in a search string, but that didn't seem to work.
More generally and less immediately, I think it would be nice to have more flexibility in what could be used to create a feed - custom fields, etc.
I'm using wp as a pseudo cms - departmental announcements, etc. It would be nice to have a feed, for example, of items categorized as "announcements" and "department X", with custom field "expire date" set to some date greater than today, and custom field "begin date" set to some date prior to the present. Basically, the same flexibility one gets in the loop with custom queries.