Storable does a binary dump. That could be an efficiency bonus or a debugging nightmare. If you want something you can inspect and read, consider either JSON or YAML.
Personally, I would recommend YAML. I've worked with both and YAML is a lot more flexible than JSON, especially when it comes to hashes. For example,
- JSON does not handle circular references safely, YAML does.
- you can control the order of hash keys much more easiliy in YAML than in JSON.
- JSON dumps blessed objects as undef or throws an exception unless the object's class has a TO_JSON method. YAML defines a default mechanism for dumping objects. If your hash key values are object references, this might be an issue.
- JSON has no syntax for encoding the class into which an object is blessed. So even if you write a TO_JSON method for the class, you will have to get creative if you want to store the class into which the hash should be blessed.
- JSON is not friendly to code ref dumps. YAML is. If your hash key values are code references, this might be an issue.
Despite a subset of nearly alike syntax, there are some small but very differences in YAML and JSON syntax. For example, YAML strings need to end with a newline. JSON barfs when they do. If you only have time to learn one, YAML will cover more use cases and take you farther.