1 <foo>
2 <bar a="1"/>
3 <bar a="1" b="2"/>
4 <bar a="1" b="2" c="3"/>
5 <bar a="1" b="2" c="3" d="4"/>
6 <bar a="1" b="2" c="3" d="4" e="5"/>
7 <bar a="1" b="2" c="3" d="4" e="5" f="6"/>
8 <bar a="1" b="2" c="3"/>
9 <bar a="1"/>
10 </foo>