They are just typedefs for the Selector widget. The API is kind of
messed up and this commit is part of the process of cleaning it up:
right now to use this, you check the is_done() method which if returns
true, the done() method executes the closure you defined when creating
the widget. The closure returns a UIEvent which you can forward
application-wide by context.replies.push_back(event) or handle it in
process_event() immediately.
Refactor Collection from melib to hold what folders have what envelopes.
Frontend accounts will now have a FolderEntry for each logical folder
and will unify many Account fields into one and eliminate a lot of
duplicate/dead code.
Use FolderHash directly as a cursor type for folders within an account
isntead of having a usize (being the order of the folder within the
account) and figuring out the folder_hash everytime it's needed.
Add OfflineListing for offline accounts and AccountStatusChange event.
Subscription status was checked/modified in various places, whereas now
the universal truth is the `BackendFolder::is_subscribed()` method set
by the backend when a folder is created. The `Account` struct passes a
closure to the backend constructor that determines whether the folder is subscribed or not according to the user configuration.
- If subscribed_folders field is empty, then all folders are subscribed.
- OR check explicit folder configuration
- OR check if folder path matches to a glob in subscribed_folders.
`DisplayMessage` messages are for user input responses (eg errors for
user actions). They now appear as floating boxes in the bottom right
corner of the UI and can be browsed with Alt('<') and Alt('>')
No logical reason for it not to be in the terminal module anymore (the
set_and_join* functions predate the terminal module which is why they
weren't there to begin with).