如何在ArkTS中使用闭包

function addNum(num1: number, num2: number): void { 
  // 使用lambda函数代替声明函数 
  let logToConsole: (message: string) => void = (message: string): void => { 
    console.log(message); 
  } 
  let result = num1 + num2; 
  logToConsole('result is ' + result); 
}