Crypto Conditions

Targeting spec: draft-thomas-crypto-conditions-02 of December 20, 2016

Current status

Supports all standard condition types except RSA.

Needs more testing. Some tests exist.

Design

This approach to Crypto Conditions in Haskell has the goals:

• Simple to understand and work with
• Easily extensible

The bottleneck to achieving these goals is extensibility; Haskell does not support dynamic dispatch like OOP languages, and runtime type casting in Haskell is very unnatural and somewhat unsafe.

The solution is to decouple the condition type from the implementation, such that the core algorithms and serialization can work with instances of an "IsCondition" class, and a polymorphic data type can be implemented separately to support the desired condition types and behaviours.

The module Network.CryptoConditions supports the standard condition types, library authors wishing to extend CryptoConditions should copy and paste this file into their own project and define their own Condition type.