ll
   also raise <code class="code"><span class="constructor">Invalid_argument</span></code> for them. Values of type <code class="code"><span class="keywordsign">'</span>a&nbsp;<span class="constructor">Lazy</span>.t</code>
   (for any <code class="code"><span class="keywordsign">'</span>a</code>) are like <code class="code">float</code> in this respect, except that the
   compiler sometimes optimizes them in a way that prevents <code class="code">finalise</code>
   from detecting them. In this case, it wi