Unless for negated conditions in Ruby - Mini Project: Build & Apply

Using <code>unless</code> for Negated Conditions in Ruby

📖 Scenario: Imagine you are building a simple program to check if a user is allowed to enter a club. The club only allows people who are not on the banned list.

🎯 Goal: You will create a Ruby program that uses the unless statement to check if a user is not banned and print a welcome message. This teaches how to use unless for negated conditions instead of if with !.

📋 What You'll Learn

Create a list called banned_users with exact names

Create a variable called user with an exact name

Use unless to check if user is not in banned_users

Print the exact welcome message if user is allowed

💡 Why This Matters

🌍 Real World

Checking if a user is allowed or blocked is common in websites, apps, and security systems.

💼 Career

Understanding <code>unless</code> helps write clear Ruby code for conditions that check for negative cases, useful in many programming jobs.

1

Create the banned users list

Create an array called banned_users with these exact names: "alice", "bob", and "charlie".

Ruby

# Create the banned_users array with 'alice', 'bob', and 'charlie'
# Your code here

Need a hint?

Use square brackets [] to create an array and separate names with commas.

2

Set the user name

Create a variable called user and set it to the string "david".

Ruby

banned_users = ["alice", "bob", "charlie"]
# Create a variable user and set it to 'david'
# Your code here

Need a hint?

Use = to assign the string "david" to user.

3

Use unless to check if user is not banned

Write an unless statement that checks if user is not included in banned_users using banned_users.include?(user).

Ruby

banned_users = ["alice", "bob", "charlie"]
user = "david"
# Use unless to check if user is not in banned_users
# Your code here

Need a hint?

Use unless banned_users.include?(user) to check if user is not banned.

4

Print the welcome message

Print the exact message "Welcome, david!" inside the unless block using puts.

Ruby

banned_users = ["alice", "bob", "charlie"]
user = "david"
unless banned_users.include?(user)
  # Print welcome message here
  # Your code here
end

Need a hint?

Use puts to print the welcome message exactly as shown.