handle_and_retry_errors.rb

def my_fun
  vals = []
  (1..5).each do |i|
    puts "my_fun i=#{i}"
    begin
      handle_catchable_errors do
        vals << unsafe_fun(i)
      end
    rescue KnownError => e
      puts "my_fun caught known error. #{e.class} #{e}. continuing"
      next
    rescue UnsafeError => e
      puts "my_fun caught unsafe error. #{e.class} #{e}. continuing"
      next
    end
  end
end

def handle_catchable_errors(max_tries: 5)
  attempt ||= 0
  attempt += 1

  puts "handle_catchable_errors attempt=#{attempt}"

  yield

rescue KnownError => e
  puts "Unsafe error ok! #{e}"
  if attempt >= max_tries
    raise e
  else
    retry
  end
rescue UnsafeError => e
  puts "Unsafe error ok! #{e}"
  if attempt >= max_tries
    raise e
  else
    retry
  end
rescue RandomError => e
  puts "RandomError not ok! #{e}"
  raise e
end

def unsafe_fun(i)

  puts "unsafe_fun i=#{i}"

  if i < 2
    raise KnownError.new("Known #{i}")
  end

  if i % 2 == 0
    raise UnsafeError.new("Unsafe #{i}")
  end

  roll = rand(1..10)
  if (roll > 8)
    raise RandomError.new("Random #{i} roll=#{roll}")
  end

  puts "Safe now i=#{i}"

  return i * -1
end

class UnsafeError < StandardError
end

class RandomError < StandardError
end

class KnownError < StandardError
end

my_fun