at</span> <span class="mdzsyn-string">"Inside myblock: %.20P"</span>})

<span class="mdzsyn-comment"># Set up a new fiber</span>
(<span class="mdzsyn-coresym">def</span> <span class="mdzsyn-symbol">f</span> (<span class="mdzsyn-coresym">fiber/new</span> <span class="mdzsyn-symbol">myblock</span>))
(<span class="mdzsyn-coresym">fiber/setenv</span> <span class="mdzsyn-symbol">f</span> (<span class="mdzsyn-coresym">table/setproto</span> <span class="mdzsyn-symbol">my-env</span> <span class="mdzsyn-symbol">curr