dentifier>a</span><span class=special>;
    </span><span class=identifier>subrule</span><span class=special>&lt;</span><span class=number>1</span><span class=special>&gt; </span><span class=identifier>b</span><span class=special>;
    </span><span class=identifier>subrule</span><span class=special>&lt;</span><span class=number>0</span><span class=special>&gt; </span><span class=identifier>c</span><span class=special>;
    </span><span class=identifier>subrule</span><span class=special>&lt;</span><span class