Lambda creation and behavior in Ruby - Mini Project: Build & Apply

Lambda creation and behavior

📖 Scenario: You are working on a small Ruby program that uses lambdas to perform simple math operations. Lambdas are like little machines that take input and give output. You will create a lambda, set up a value to use with it, run the lambda, and then show the result.

🎯 Goal: Build a Ruby program that creates a lambda to double a number, applies it to a given number, and prints the result.

📋 What You'll Learn

Create a lambda called double that takes one argument and returns it multiplied by 2

Create a variable called number and set it to 7

Call the double lambda with number as input and store the result in doubled_number

Print the value of doubled_number

💡 Why This Matters

🌍 Real World

Lambdas are useful for small tasks you want to reuse, like math operations or filtering lists.

💼 Career

Understanding lambdas helps you write cleaner, more flexible Ruby code, which is valuable in many programming jobs.

1

Create a lambda called double

Create a lambda called double that takes one argument named x and returns x * 2.

Ruby

# Create a lambda called double that doubles its input
# Your code here

Need a hint?

Use ->(x) { } to create a lambda in Ruby.

2

Create a variable number with value 7

Create a variable called number and set it to 7.

Ruby

double = ->(x) { x * 2 }
# Create a variable number and set it to 7
# Your code here

Need a hint?

Just write number = 7 to store the number.

3

Call the lambda and store the result

Call the lambda double with number as input and store the result in a variable called doubled_number.

Ruby

double = ->(x) { x * 2 }
number = 7
# Call double with number and store in doubled_number
# Your code here

Need a hint?

Use double.call(number) to run the lambda.

4

Print the doubled number

Print the value of doubled_number using puts.

Ruby

double = ->(x) { x * 2 }
number = 7
doubled_number = double.call(number)
# Print doubled_number
# Your code here

Need a hint?

Use puts doubled_number to show the result.