How to clear the field in the VBS defaulting rule in JS code?

Summary:

How to clear the field in the VBS defaulting rule in JS code?

Content (please ensure you mask any confidential information):

Hi experts,

I am trying to migrate the autocomplete field modification rules to VBS. This is extremely challenging. I would say mostly impossible.

I would suggest sharing the experience on this.

I am faced with the following issues and have questions to ask:

1. How is it possible to clear a field value in the advanced expression of the defaulting rule

Below is the code:

/* eslint-disable dot-notation */
define([], () => {
  'use strict';

  /**
   * Default value expression for employmentAssignments.assignmentsDFF.iPayBuChar
   * @param {object} context
   * @return {string}
   */
  function getEmploymentAssignmentsAssignmentsDFFIPayBuChar(context) {
    const { $fields } = context;

    const l4 =
      $fields.employmentAssignments.departmentsLov.departmentsDFF.l4.$value();
    const dc =
      $fields.employmentAssignments.departmentsLov.departmentsDFF.iDepartmentCode.$value();
    const legalEntity =
      $fields.employmentAssignments.legalEntitiesLov.Name.$value();
    console.log('DEFAULTING start...');
    console.log('Legal Entity:', legalEntity);
    console.log('L4:', l4);