Exception Handling in Ruby: A Beginner's Guide
Introduction to Exception Handling
Exception handling is a crucial aspect of programming that allows you to gracefully handle errors and unexpected situations in your code. In Ruby, exceptions are objects that represent errors. Exception handling enables you to write code that can recover from errors and provide a better user experience. In this guide, we'll explore the basics of exception handling in Ruby with examples.
Types of Exceptions
Ruby has a wide variety of built-in exceptions. Here are some common types of exceptions:
begin
# Code that may raise an exception
result = 10 / 0
rescue ZeroDivisionError
puts "Division by zero error!"
end
In this example, a ZeroDivisionError
exception is raised because we are attempting to divide by zero. The rescue
block catches the exception and provides an error message.
Handling Exceptions
You can use the begin
and rescue
blocks to handle exceptions and gracefully recover from errors. Here's an example:
begin
result = 10 / 0
rescue ZeroDivisionError
puts "Division by zero error! Setting result to 0."
result = 0
end
puts "Result: #{result}"
In this example, the rescue
block handles the ZeroDivisionError
by setting the result to 0 instead of crashing the program.
Raising Exceptions
You can also raise exceptions explicitly using the raise
keyword. Here's an example:
def check_age(age)
if age < 18
raise ArgumentError, "You must be at least 18 years old."
end
end
begin
check_age(15)
rescue ArgumentError => e
puts "Error: #{e.message}"
end
In this example, the check_age
method raises an ArgumentError
if the age is less than 18. The rescue
block catches the exception and displays the error message.
Conclusion
Exception handling is a vital skill for writing robust and reliable Ruby programs. It allows you to manage errors, handle unexpected situations, and ensure a better user experience. By understanding the basics of exception handling, you can write code that gracefully recovers from errors.
Practice exception handling in your Ruby programs to become a proficient Ruby developer. For more information, refer to the official Ruby documentation.
Happy coding!