Tricky Outputs — Series 2

Preview — 3 of 10 questions

Assume this executes as a classic, non-strict script. What is the output?

javascript

const config = Object.freeze({ name: 'app', settings: { debug: true } });

config.name = 'changed';
config.settings.debug = false;

console.log(config.name);
console.log(config.settings.debug);

A"changed", false

B"app", false

C"app", true

D"changed", true

What is the output?

javascript

const nums = [10, 1, 21, 2];
nums.sort();
console.log(nums);

A[10, 1, 21, 2]

B[1, 2, 10, 21]

C[21, 10, 2, 1]

D[1, 10, 2, 21]

What is logged?

javascript

function tag(strings, ...values) {
  return strings.reduce((result, str, i) => {
    return result + str + (values[i] !== undefined ? `[${values[i]}]` : '');
  }, '');
}

const name = 'Alice';
const age = 30;

console.log(tag`Name: ${name}, Age: ${age}`);

ATypeError: strings.reduce is not a function

B"Name: , Age: "

C"Name: [Alice], Age: [30]"

D"Name: Alice, Age: 30"

Answer all 10 questions (7 more), see explanations for every answer, and track your score.