Attempts to invoke a function with the provided arguments, returning either the result or the caught error object.
- Use a 
try...catchblock to return either the result of the function or an appropriate error. - If the caught object is not an 
Error, use it to create a newError. 
代码实现
const attempt = (fn, ...args) => {
  try {
    return fn(...args);
  } catch (e) {
    return e instanceof Error ? e : new Error(e);
  }
};
let elements = attempt(function(selector) {
  return document.querySelectorAll(selector);
}, '>_>');
if (elements instanceof Error) elements = []; // elements = []
翻译自:https://www.30secondsofcode.org/js/s/attempt-invoking-function