code: public static WhenBuilder arrayWithin(Expression arrayExpression, String variable, Expression expression) {
          return new WhenBuilder(x("ARRAY " + arrayExpression.toString() + " FOR"),
                  variable, expression, false);
      }
docs: Create an ARRAY comprehension with a first WITHIN range.
  
  The ARRAY operator lets you map and filter the elements or attributes of a collection, object, or objects.
  It evaluates to an array of the operand expression, that satisfies the WHEN clause, if provided.
  
  For elements, IN ranges in the direct elements of its array expression, WITHIN also ranges in its descendants.