mozilla/rust — pull request #13230 by Kroisse (2014-03-31 18:05:23+00:00)
Title: Json doesn't need to depend on IoError to implement Encodable

The implementation of `Encodable` for `Json` didn't assume `S` to be `IoError`, only the default encoders for `Json` are depend on it. So this can be parametrize to increase flexiblity. If not, types that implement `Encoder` where `E` is not `IoError` can't be worked with `Json`.