ArkTS是否支持多继承
============

接口支持多继承，类仅支持单继承。示例如下：

class TestClassA {
  address: string = '';
}

class TestClassB {
  name: string = '';
}

_// report errors：Classes can only extend a single class._
_// class TestClassC extends TestClassA, TestClassB {_
_// }_

interface AreaSize {
  calculateAreaSize(): number;
}

interface Cal {
  Sub(a: number, b: number): number;
}

interface Area extends AreaSize, Cal {
  areaName: string;
  length: number;
  width: number;
}