Understanding Fetch - Exercises

Five exercises to make sure everything clicks before moving into CRUD.

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Exercise 1 - Arrow Functions

Rewrite all four of these as arrow functions:

function triple(n) {
    return n * 3
}

function fullName(first, last) {
    return first + " " + last
}

function isEven(n) {
    return n % 2 === 0
}

function shout(text) {
    let upper = text.toUpperCase()
    return upper + "!"
}

Call each one with a test value and log the result to confirm it works.

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Exercise 2 - Your First Fetch

Write a fetch call that loads a single post from https://jsonplaceholder.typicode.com/posts/1.

Use arrow functions. When the data arrives, log the title and body fields separately.

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Exercise 3 - Adding Error Handling

Take the fetch call from Exercise 2 and add .catch() to it. The catch should log the error message to the console.

Then test it - change the URL to https://jsonplaceholder.typicode.com/notarealpath and confirm your .catch() fires.

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Exercise 4 - Finally

Add .finally() to your fetch call from Exercise 3. It should log "Request finished" whether the fetch succeeded or failed.

Run it twice - once with a working URL, once with a broken one. Confirm "Request finished" appears both times.

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Exercise 5 - Fetching a List

Fetch all users from https://jsonplaceholder.typicode.com/users. When the data arrives:

• Log how many users there are
• Loop through them and log each user's name and email
• Include .catch() and .finally()

Write the whole thing from scratch using arrow functions throughout.

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