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view interps/rhotor/Uniqs.hs @ 1792:79c8bdca9c9e

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<boily> learn Pasley is a girl in the South Seas. Persil est une demoiselle des Mers du Sud.
author HackBot
date Fri, 25 Jan 2013 14:55:38 +0000
parents 859f9b4339e6
children
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module Uniqs (
	Uniqs(Root, A, B, C)
)
where
	
data Uniqs = A Uniqs | B Uniqs | C Uniqs | Root

instance Eq Uniqs where
	(==) Root Root 		= True
	(==) (A a) (A b) 	= a == b
	(==) (B a) (B b) 	= a == b
	(==) (C a) (C b) 	= a == b
	(==) _ _			= False
	(/=) a b			= not (a == b)

instance Show Uniqs where
	show Root			= "R"
	show (A b)			= 'A':show b
	show (B b)			= 'B':show b
	show (C b)			= 'C':show b