gle" id="literate-lean3-lean-chk0" style="display: none" type="checkbox"><label class="alectryon-input" for="literate-lean3-lean-chk0"><span class="k">#reduce</span> <span class="k">let</span> x := <span class="mi">5</span> <span class="k">in</span> x <span class="bp">+</span> <span class="mi">3</span></label><small class="alectryon-output"><div><div class="alectryon-messages"><blockquote class="alectryon-message"><span class="mi">8</span></blockquote></div></div></small></span></pre><p>By default, these re