Excluding Multiple Files in Org-mode Export Function

Question

I'm trying to find the way to exclude multiple files from export tree. For instance, in the following example in org-publish-project-alist, I have level-0.org excluded, so it won't be created in /foo/bar/pub as well as not in the sitemap.

("somewebproject" 
   :base-directory "/foo/bar/src"
   :base-extension "org"
   :publishing-directory "/foo/bar/pub"
   :recursive t
   :exclude "level-0.org" 
   :publishing-function org-html-publish-to-html
   :headline-levels 4 ; Just the default for this project.
   :auto-preamble t
   :auto-sitemap t
   :html-link-up "sitemap.html"
   :html-link-home "index.html"
   :sitemap-title "My Sitemap"
)

However, I have an another file called, for example level-1.org that I also want to exclude, making the file into the list, for instance '("level-0.org" "level-1.org") doesn't seem to help it either.

Any tips on making it work in the this snippet, or if there are better ways of doing this, that would be highly appreciated!

Answer 1

I found a solution, after reading actual org-mode source code. So I'm answering my own question here.

In short, looks like :exclude accepts regular expression, so I could do level-0.org\\|level-1.org or in this case level-..org.