# `empty` `empty` checks if a variable is empty: <table class="highlighttable"><tr><td class="linenos"><div class="linenodiv"><pre>1 2 3 4</pre></div></td><td class="code"><div class="highlight"><pre>{# evaluates to true if the foo variable is null, false, an empty array, or the empty string #} {% if foo is empty %} ... {% endif %} </pre></div></td></tr></table>