ern 3: Dynamic Rule Creation and Execution</strong></h3>
<p>Create rules dynamically and execute them immediately.</p>
<h4 id="3a-dynamic-rule-addition-to-list-objects"><strong>3a. Dynamic Rule Addition to $LIST Objects</strong></h4>
<div class="highlight"><pre><span></span><code>/* Start with base ETL rules object */
etl_rules = {
    parse = op(parse_data, parse_rule){op()(parse_data, parse_rule)()},
};

/* Dynamically add new rules using += operator */
etl_rules += (csv_parser : rule $ID &#39;,&#39; $INT