intridea/multi_json — pull request #129 by tooky (2013-06-28 16:07:00+00:00)
Title: Prevent warning for uninitialized `@cached_options`

The current implementation is generating a warning because `@cached_options` hasn't been initialized when it's first called.

```
~/.gem/ruby/1.9.3/gems/multi_json-1.7.7/lib/multi_json.rb:10: warning: instance variable @cached_options not initialized
```

Using the `||=` operator prevents this warning, even though it seems like its doing the assignment twice. Not sure if there's a better option?