39 lines
437 B
Markdown
39 lines
437 B
Markdown
Maybe
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=====
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```haskell
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maybe :: b -> (a -> b) -> Maybe a -> b
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```
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```haskell
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isJust :: Maybe a -> Bool
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```
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```haskell
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isNothing :: Maybe a -> Bool
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```
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```haskell
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fromJust :: Maybe a -> a
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```
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```haskell
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fromMaybe :: a -> Maybe a -> a
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```
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```haskell
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listToMaybe :: [a] -> Maybe a
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```
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```haskell
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maybeToList :: Maybe a -> [a]
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```
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```haskell
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catMaybes :: [Maybe a] -> [a]
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```
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```haskell
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mapMaybe :: (a -> Maybe b) -> [a] -> [b]
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```
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