JavaScript样式指南变量声明

Question

Does anyone know why on the airbnb style guide this one is bad, while the other one is good? I would expect the 'name' variable to hoisted, like the previous example.

thanks in advance.

Here's a link. https://github.com/airbnb/javascript#variables

// bad
function() {
  var name = getName();

  if (!arguments.length) {
    return false;
  }

  return true;
}

// good
function() {
  if (!arguments.length) {
    return false;
  }

  var name = getName();

  return true;
}

Answer 1

Because if !arguments.length is true , you don't want to execute the rest of the function anyway, so there's no point in calling the function getName(); when assigning the variable that you'd never use when !arguments.length .