chpatrick/haskell-capnp

Cap'n Proto for Haskell

A Haskell library for the Cap'N Proto Cerialization protocol.

Serialization (read & write) support is mostly finished, and already usable, with some limitations:

• Generated schema currently ignore type parameters (#29).
• Schema which define custom default values for fields of pointer type are rejected (#28).
• We currently do not correctly handle decoding lists of structs from non-composite lists (#27). This means that, contrary to the protocol evolution rules, it is not safe to change a field from type List(T) (where T is any non-struct type) to a list of a struct type.

There is a module Capnp.Tutorial which contains an introduction to the library; users are strongly encouraged to read this first, as the reference documentation can be bewildering without that context.

The API is considered unstable. It will likely see changes, for the sake of polish, consistency, etc. as well as to improve performance and accommodate more features as we add them (RPC in particular will probably require changing some interfaces).