Rescue modifier (inline form) in Ruby - Mini Project: Build & Apply

Rescue Modifier (Inline Form) in Ruby

📖 Scenario: Imagine you are writing a small program that tries to convert user input into a number. Sometimes, the input might not be a valid number, and your program should handle that gracefully without crashing.

🎯 Goal: You will build a Ruby program that uses the rescue modifier (inline form) to handle errors when converting strings to integers.

📋 What You'll Learn

Create a variable called user_input with the exact string value "abc"

Create a variable called number that tries to convert user_input to an integer using Integer(user_input) but uses the rescue modifier to assign 0 if an error occurs

Use the rescue modifier (inline form) exactly as expression rescue value

Print the value of number using puts

💡 Why This Matters

🌍 Real World

When accepting user input, programs often need to handle invalid data without crashing. Rescue modifier helps keep programs running smoothly by providing fallback values.

💼 Career

Understanding error handling is important for writing robust Ruby applications, especially in web development and scripting.

1

Create the user input variable

Create a variable called user_input and set it to the string "abc" exactly.

Ruby

# Create a variable called user_input with the string "abc"
# Your code here

Need a hint?

Use = to assign the string "abc" to user_input.

2

Use rescue modifier to convert input

Create a variable called number that tries to convert user_input to an integer using Integer(user_input) but uses the rescue modifier (inline form) to assign 0 if an error occurs. Use the exact syntax: Integer(user_input) rescue 0.

Ruby

user_input = "abc"
# Create variable number using rescue modifier to convert user_input to integer or 0
# Your code here

Need a hint?

Use Integer(user_input) rescue 0 to handle invalid input gracefully.

3

Try with a valid number string

Change the value of user_input to the string "123" exactly. Keep the number assignment the same using the rescue modifier.

Ruby

user_input = "abc"
number = Integer(user_input) rescue 0
# Change user_input to "123"
# Your code here

Need a hint?

Just replace the string value assigned to user_input with "123".

4

Print the result

Use puts to print the value of the variable number.

Ruby

user_input = "123"
number = Integer(user_input) rescue 0
# Print the value of number
# Your code here

Need a hint?

Use puts number to display the number.