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| author | Joe Zhao <ztuowen@gmail.com> | 2015-03-26 01:47:10 +0800 |
|---|---|---|
| committer | Joe Zhao <ztuowen@gmail.com> | 2015-03-26 01:47:10 +0800 |
| commit | 36a645180f3ef13126c06b957d76c729f62d41fd (patch) | |
| tree | 98658a7823bf3ccf3828f460dde85a694ba730a8 /applicative/h1.hs | |
| parent | 934eda548d1f0260db095f2739b2211bd5157324 (diff) | |
| download | typeclass-36a645180f3ef13126c06b957d76c729f62d41fd.tar.gz typeclass-36a645180f3ef13126c06b957d76c729f62d41fd.tar.bz2 typeclass-36a645180f3ef13126c06b957d76c729f62d41fd.zip | |
applicative h1 h2
Diffstat (limited to 'applicative/h1.hs')
| -rw-r--r-- | applicative/h1.hs | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/applicative/h1.hs b/applicative/h1.hs new file mode 100644 index 0000000..b13c33d --- /dev/null +++ b/applicative/h1.hs @@ -0,0 +1,14 @@ +import Control.Applicative + +data MyMaybe a = MyNothing | MyJust a + deriving (Show) + +instance Functor MyMaybe where + fmap _ MyNothing = MyNothing + fmap f (MyJust x) = MyJust (f x) + +instance Applicative MyMaybe where + pure x = MyJust x + MyNothing <*> _ = MyNothing + _ <*> MyNothing = MyNothing + (MyJust f) <*> (MyJust g) = MyJust (f g) |