Range operators (.. and ...) in Ruby - Mini Project: Build & Apply

Range operators (.. and ...)

📖 Scenario: You are organizing a small library and want to select books by their ID numbers. You will use Ruby's range operators to pick books within certain ID ranges.

🎯 Goal: Learn how to create ranges using the .. and ... operators and understand the difference between inclusive and exclusive ranges.

📋 What You'll Learn

Create a range of book IDs using the inclusive range operator ..

Create a range of book IDs using the exclusive range operator ...

Use a for loop to iterate over the inclusive range

Print the ranges to see the difference in output

💡 Why This Matters

🌍 Real World

Ranges are useful when you want to select a sequence of items, like book IDs, page numbers, or dates, without listing each item individually.

💼 Career

Understanding ranges helps in data filtering, pagination, and working with sequences in many programming jobs.

1

Create an inclusive range of book IDs

Create a variable called inclusive_range that holds a range of book IDs from 1 to 5 using the inclusive range operator ...

Ruby

# Create an inclusive range of book IDs from 1 to 5
# Your code here

Need a hint?

Use .. to include the last number in the range.

2

Create an exclusive range of book IDs

Create a variable called exclusive_range that holds a range of book IDs from 1 to 5 using the exclusive range operator ....

Ruby

inclusive_range = 1..5
# Create an exclusive range of book IDs from 1 to 5
# Your code here

Need a hint?

Use ... to exclude the last number in the range.

3

Iterate over the inclusive range

Use a for loop with the variable book_id to iterate over inclusive_range and print each book_id.

Ruby

inclusive_range = 1..5
exclusive_range = 1...5
# Use a for loop to print each book_id in inclusive_range
# Your code here

Need a hint?

Use for book_id in inclusive_range and puts book_id inside the loop.

4

Print both ranges to compare

Print inclusive_range.to_a and exclusive_range.to_a to see the difference between the two ranges.

Ruby

inclusive_range = 1..5
exclusive_range = 1...5
for book_id in inclusive_range
  puts book_id
end
# Print both ranges as arrays
# Your code here

Need a hint?

Use puts inclusive_range.to_a and puts exclusive_range.to_a to print the ranges as arrays.