massage_ch_ex.baseline

<?xml version="1.0" encoding="UTF-8"?>
<bgf:grammar xmlns:bgf="http://planet-sl.org/bgf">
  <bgf:production>
    <nonterminal>foo</nonterminal>
    <bgf:expression>
      <optional>
        <bgf:expression>
          <nonterminal>bar</nonterminal>
        </bgf:expression>
      </optional>
    </bgf:expression>
  </bgf:production>
</bgf:grammar>