handling With a message in Ruby

In Ruby, begin, rescue, ensure, else are used to implement try/catch/finally blocks. Here is an example on how to use them with a message:

begin
  # this block contains code that might raise an exception
  age = 17
  raise ArgumentError, "Age should be greater than or equal to 18." if age < 18
rescue ArgumentError => e
  # this block will catch the exception
  puts "Error: #{e.message}"
else
  # this block will execute only if there is no exception
  puts "Welcome!"
ensure
  # this block will always execute, regardless of whether there
  # was an exception raised or not
  puts "Thank you for using our application."
end

In this example, begin, rescue, ensure, else have been used to create a try/catch/finally block. The begin block contains the code that might raise an exception. In this case, we are checking if the age is less than 18 and raising an ArgumentError with a custom message if it is.

The rescue block will catch any exception thrown by the code in the begin block and provide a customized error message using e.message. The else block will execute only if there is no exception.

The ensure block will always execute, regardless of whether there was an exception raised or not. In this case, it simply prints a thank you message.