ss="ruby-operator">-</span> <span class="ruby-identifier">pos</span>
        <span class="ruby-identifier">str</span>   = <span class="ruby-identifier">text</span>[<span class="ruby-identifier">pos</span>, <span class="ruby-identifier">len</span>]
        <span class="ruby-identifier">pos</span>   = <span class="ruby-identifier">match</span>.<span class="ruby-identifier">end</span>(<span class="ruby-value">0</span>)
        <span class="ruby-keyword kw">if</span> <span class="ruby-identifier">text2</span>.<