ArkTS中没有any类型，大家都是如何定义动态类型的

type Dynamic = string | number | boolean;
function handle(val: Dynamic) {
  if (typeof val === 'string') {
    // 处理字符串
  }
}

const dynamicObj: Record<string, unknown> = {
  key: "value",
  count: 123
};

const data = JSON.parse(jsonStr) as MyInterface;

class Base {}
class SubA extends Base {}
class SubB extends Base {}
const arr: Base[] = [new SubA(), new SubB()];