view interps/rhotor/Uniqs.hs @ 6842:76c0c1881313

<olsner> learn The internet is for everything. However many thing can done even without internet too, often better without use of internet, but internet is good too.
author HackBot
date Mon, 15 Feb 2016 01:09:11 +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