javascript - 使用默认参数调用也有回调的函数

Question

考虑示例代码:

function makeRequest(endpoint, form = {}, qs = {}, callback) {
  const exampleObject = {
    endpoint,
    form,
    qs,
  };
  callback(exampleObject);
}

makeRequest('/example', { foo: 'string' }, { bar: 'string' }, (exampleObject) => {
  console.log(exampleObject);
});

在上面的示例中，以下对象将记录在控制台上:

{ endpoint: '/example',
  form: { foo: 'string' },
  qs: { bar: 'string' } }

如何在 makeRequest 中使用默认设置并仍然使用回调？例如，以下失败:

makeRequest('/example', (exampleObject) => {
  console.log(exampleObject);
});

输出:

/Users/daniel/example.js:13
  callback(exampleObject);
  ^

TypeError: callback is not a function
    at makeRequest (example.js:7:3)
    at Object.<anonymous> (example.js:10:1)
    at Module._compile (module.js:409:26)
    at loader (/usr/local/lib/node_modules/babel-cli/node_modules/babel-register/lib/node.js:148:5)
    at Object.require.extensions.(anonymous function) [as .js] (/usr/local/lib/node_modules/babel-cli/node_modules/babel-register/lib/node.js:158:7)
    at Module.load (module.js:343:32)
    at Function.Module._load (module.js:300:12)
    at Function.Module.runMain (module.js:441:10)
    at /usr/local/lib/node_modules/babel-cli/lib/_babel-node.js:160:24
    at Object.<anonymous> (/usr/local/lib/node_modules/babel-cli/lib/_babel-node.js:161:7)

考虑到我只发送一个参数，这是有道理的。我想知道如何在利用默认参数的同时调用 makeRequest 并仍然获得回调。如果回调存在，我是否总是必须传递三个参数？有没有其他方法可以解决这个问题，所以我可以选择仅在需要时使用第二个和第三个参数，并且始终在回调中获取 exampleObject？

Answer 1

destructuring怎么样？ ？

function makeRequest({ endpoint, form = {}, qs = {}, callback = () => {} }) {
  const exampleObject = {
    endpoint,
    form,
    qs,
  };

  callback(exampleObject);
}

makeRequest({
  endpoint: '/example',
  callback: (x) => console.log(x)
});