til/ruby/what-to-do-when-you-dont-rescue.md

What To Do When You Don't Rescue

Ruby's rescue syntax supports a couple different blocks. I was already familiar with ensure which is a block of code that will be executed regardless of whether or not an exception was rescued.

begin
  do_something_that_could_fail()
rescue StandardError => e
  # oh no!
ensure
  Logging.info("We attempted to do the thing.")
end

What if you want to differentiatee between an instance when your code ran without incident and when there was an exception? Ruby's rescue syntax also supports an else block. The else block is executed only when nothing is rescued.

begin
  do_something_that_could_fail()
rescue StandardError => e
  Logging.info("We tried to do something and it failed.")
else
  Logging.info("We successfully did the thing!")
end

There are a lot of ways to use this. Here I was able to differentiate the messaging in my logging based on whether or not an exception occurred.

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