From e70cbe42352eca64aa4c0cf1658a5a561b5a5f35 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Wed, 14 Oct 2015 10:57:25 -0400
Subject: [PATCH] Algebraic hashing over cofrees of Hashable types.

---
 prototype/Doubt/Cofree.swift | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/prototype/Doubt/Cofree.swift b/prototype/Doubt/Cofree.swift
index 0704a779e..52b34c0a0 100644
--- a/prototype/Doubt/Cofree.swift
+++ b/prototype/Doubt/Cofree.swift
@@ -87,5 +87,11 @@ extension Cofree {
 	}
 }
 
+extension Cofree where A: Hashable, B: Hashable {
+	public var hash: Hash {
+		return hash(annotation: Hash.init, leaf: Hash.init)
+	}
+}
+
 
 import Prelude