Siren: a JSONQuery interpreter for Ruby
Anyway, Siren lets you run queries against any type of Ruby object. In addition to the standard JSONQuery features, Siren allows JSON objects to be assigned IDs, enabling cross referencing and cyclic data structures. It also allows you to tell the parser to cast objects to an instance of a particular type, populating instance variables with the data (rather than just using vanilla hashes or arrays like most JSON tools).
Siren is available on James's Github account. Check out the README for more details on the supported features.
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