gistfile1.clj

(clojure.xml/emit {:tag :FOO
                   :attrs {:attr 'xxx},
                   :content [{:tag :BAR
                              :attrs {:name "bar", :num 123}}
                             {:tag :BAR
                              :attrs {:name "baz", :num 100}}]})
<?xml version='1.0' encoding='UTF-8'?>
<FOO attr='xxx'>
<BAR name='bar' num='123'/>
<BAR name='baz' num='100'/>
</FOO>