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annotate similer.hs @ 3:3c5fbce357af

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Define >>= for Similer
author Yasutaka Higa <e115763@ie.u-ryukyu.ac.jp>
date Sun, 31 Aug 2014 19:21:42 +0900
parents a5210ec1e41b
children 66609010d477
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3c5fbce357af Define >>= for Similer
Yasutaka Higa <e115763@ie.u-ryukyu.ac.jp>
parents: 2
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1 {-# LANGUAGE UndecidableInstances #-}
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a5210ec1e41b Reduce definition
Yasutaka Higa <e115763@ie.u-ryukyu.ac.jp>
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2 data Similer a b = Similer a (a -> b) b
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Yasutaka Higa <e115763@ie.u-ryukyu.ac.jp>
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4 instance Functor (Similer a) where
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5 fmap g (Similer a f b) = Similer a (g . f) $ g b
7a82a5e50499 Initial commit. define to Functor for Similer
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Yasutaka Higa <e115763@ie.u-ryukyu.ac.jp>
parents: 2
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7 same :: (Eq a) => Similer a b -> Similer a b -> Bool
3c5fbce357af Define >>= for Similer
Yasutaka Higa <e115763@ie.u-ryukyu.ac.jp>
parents: 2
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8 same (Similer a _ _ ) (Similer b _ _) = a == b
3c5fbce357af Define >>= for Similer
Yasutaka Higa <e115763@ie.u-ryukyu.ac.jp>
parents: 2
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Yasutaka Higa <e115763@ie.u-ryukyu.ac.jp>
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10 eta :: a -> Similer a a
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parents:
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11 eta a = Similer a id a
7a82a5e50499 Initial commit. define to Functor for Similer
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3c5fbce357af Define >>= for Similer
Yasutaka Higa <e115763@ie.u-ryukyu.ac.jp>
parents: 2
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13 mu :: (Eq b) => Similer a (Similer b c) -> Similer b c
3c5fbce357af Define >>= for Similer
Yasutaka Higa <e115763@ie.u-ryukyu.ac.jp>
parents: 2
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14 mu (Similer a f b) = if (same (f a) b) then b else undefined
3c5fbce357af Define >>= for Similer
Yasutaka Higa <e115763@ie.u-ryukyu.ac.jp>
parents: 2
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3c5fbce357af Define >>= for Similer
Yasutaka Higa <e115763@ie.u-ryukyu.ac.jp>
parents: 2
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16 instance (Eq a) => Monad (Similer a) where
3c5fbce357af Define >>= for Similer
Yasutaka Higa <e115763@ie.u-ryukyu.ac.jp>
parents: 2
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17 --return x = Similer x id x
3c5fbce357af Define >>= for Similer
Yasutaka Higa <e115763@ie.u-ryukyu.ac.jp>
parents: 2
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18 s >>= f = mu (fmap f s)