(unless (string-match-p "^[-+]\\S-+$" tag-change)
(error "Tag must be of the form `+this_tag' or `-that_tag'")))
tag-changes)
+ (unless query
+ (error "Nothing to tag!"))
(unless (null tag-changes)
(run-hooks 'notmuch-before-tag-hook)
(if (<= (length query) notmuch-tag-argument-limit)