Add Retry A Block After An Exception as a Ruby til

ruby/retry-a-block-after-an-exception.md

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+# Retry A Block After An Exception
+
+Ruby comes with a [_retry_
+mechanism](https://ruby-doc.org/docs/keywords/1.9/Object.html#method-i-retry)
+that allows you to recover from known exceptions by retrying the code that led
+to the exception. In network or timing-based situations where race conditions
+are possible, the most straightforward recourse may be to just _retry_ a couple
+times.
+
+Set up a `begin` / `rescue` block like you'd normally do for a chunk of code
+that may raise an exception. Then add a `retry` call to the `rescue` block.
+
+```ruby
+begin
+  puts "About to do a thing (#{retries})"
+
+  raise StandardError if rand(5) != 4
+
+  puts "Success!"
+rescue StandardError => e
+  retry
+end
+```
+
+If an exception is raised, this will tell Ruby to re-execute the code in the
+`begin` block over and over until the exception isn't raised.
+
+To avoid an infinite loop, you can limit the retries with a counting variable.
+
+```ruby
+begin
+  retries ||= 0
+  puts "About to do a thing (#{retries})"
+
+  raise StandardError if rand(5) != 4
+
+  puts "Success!"
+rescue StandardError => e
+  retry if (retries += 1) < 3
+
+  # all retries failed, re-raise exception
+  raise e
+end
+```
+
+This will re-raise after 3 tries.
+
+Here is the [full example](https://gist.github.com/jbranchaud/629fb3b9d55c817e5c9fc480790dfabc)
+
+[source](https://www.honeybadger.io/blog/how-to-try-again-when-exceptions-happen-in-ruby/)