This book looks great!

I tried to implement this in Ruby with a gem about 6 years ago and got really close. If anyone wants to know more about this, but is more fluent in Ruby, you might find this a good jumping-off point. There’s a good explanation in the README.

  https://github.com/michaeljbishop/mulligan

Why did it not work in the end? Because even though I was able to implement an error-recovery mechanism that wouldn’t pop the stack, it still triggered all the `ensure` statements that were up the stack. It was still a valuable exercise. I'd welcome this addition in any exception-based language.