What is the Ruby equivalent of Python's try statement?

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1

What is the Ruby equivalent of Python’s try statement?

I’m converting some Python code to Ruby and need to handle exceptions. Does Ruby have a try-catch mechanism similar to Python’s try-except? If so, how does Ruby try-catch work?

2

In Python, you use try-except to handle exceptions. Ruby has a similar mechanism using begin-rescue.

Here’s how it works:

begin
  # Code that may raise an exception
  num = 10 / 0
rescue ZeroDivisionError => e
  puts "Error: #{e.message}"
end

This is equivalent to:

try:
    num = 10 / 0
except ZeroDivisionError as e:
    print(f"Error: {e}")

The begin block contains the code that might fail, and rescue catches the error."

3

That’s a good start! Ruby also allows handling multiple exception types, just like Python:

begin
  # Some risky operation
  raise ArgumentError, "Invalid argument"
rescue ZeroDivisionError
  puts "Caught division by zero"
rescue ArgumentError => e
  puts "Caught argument error: #{e.message}"
end

Additionally, Ruby has an ensure block, which is similar to Python’s finally. This is useful for cleanup tasks like closing files or releasing resources: This guarantees that ensure runs no matter what happens in begin or rescue."

4

Building on that, if you want to raise custom exceptions, Ruby provides raise, just like Python’s raise:

def check_age(age)
  raise ArgumentError, "Age must be greater than 18" if age < 18
end

begin
  check_age(16)
rescue ArgumentError => e
  puts "Caught an error: #{e.message}"
end

If you need more structured exception handling, you can even define custom exception classes: class CustomError < StandardError; end

begin
  raise CustomError, "Something went wrong!"
rescue CustomError => e
  puts "Caught custom error: #{e.message}"
end