code: function isScalarAndEqual(valueA: mixed, valueB: mixed): boolean {
    return valueA === valueB && (valueA === null || typeof valueA !== 'object');
  }
docs: A fast test to determine if two values are equal scalars:
  - compares scalars such as booleans, strings, numbers by value
  - compares functions by identity
  - returns false for complex values, since these cannot be cheaply tested for
  equality (use `areEquals` instead)