Function notmuch_sys::notmuch_messages_collect_tags

pub unsafe extern "C" fn notmuch_messages_collect_tags(
    messages: *mut notmuch_messages_t
) -> *mut notmuch_tags_t

Return a list of tags from all messages.

The resulting list is guaranteed not to contain duplicated tags.

WARNING: You can no longer iterate over messages after calling this function, because the iterator will point at the end of the list. We do not have a function to reset the iterator yet and the only way how you can iterate over the list again is to recreate the message list.

The function returns NULL on error.