a>.Int64.t</code></td></tr><tr id="type-template_arg.TNull" class="anchored"><td class="def constructor"><a href="#type-template_arg.TNull" class="anchor"></a><code>| </code><code><span class="constructor">TNull</span></code></td></tr><tr id="type-template_arg.TNullPtr" class="anchored"><td class="def constructor"><a href="#type-template_arg.TNullPtr" class="anchor"></a><code>| </code><code><span class="constructor">TNullPtr</span></code></td></tr><tr id="type-template_arg.TOpaque" class="anchored"><td clas