Materialize/doc/user/layouts/shortcodes/list-operators.html

Operator | Description
---------|-------------
<code>listany &vert;&vert; listany</code> | Concatenate the two lists.
<code>listany &vert;&vert; listelementany</code> | Append the element to the list.
<code>listelementany &vert;&vert; listany</code> | Prepend the element to the list.
<code>listany @&gt; listany</code> | Check if the first list contains all elements of the second list.
<code>listany &lt;@ listany</code> | Check if all elements of the first list are contained in the second list.