115 lines
1.0 KiB
Markdown
115 lines
1.0 KiB
Markdown
Functions
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=========
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Composition
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-----------
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#### $
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```haskell
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($) :: (a -> b) -> a -> b
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```
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*Example*:
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#### .
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```haskell
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(.) :: (b -> c) -> (a -> b) -> a -> c
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```
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*Example*:
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#### &
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```haskell
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(&) :: a -> (a -> b) -> b
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```
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*Example*:
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#### flip
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```haskell
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flip :: (a -> b -> c) -> b -> a -> c
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```
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*Example*:
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#### on
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```haskell
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on :: (b -> b -> c) -> (a -> b) -> a -> a -> c
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```
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*Example*:
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#### const
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```haskell
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const :: a -> b -> a
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```
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*Example*:
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#### fix
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```haskell
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fix :: (a -> a) -> a
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```
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*Example*:
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#### identity
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```haskell
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identity :: a -> a
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```
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The identity function maps any value to itself.
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#### applyN
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Apply a function to a value `n` times.
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*Example*:
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```haskell
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applyN :: Int -> (a -> a) -> a -> a
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```
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```haskell
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> applyN 25 (+2) 0
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50
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> applyN 3 (1:) []
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[1,1,1]
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```
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Strictness
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-----------
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#### $!
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```haskell
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($!) :: NFData a => (a -> b) -> a -> b
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```
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*Example*:
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#### $!!
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```haskell
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($!!) :: NFData a => (a -> b) -> a -> b
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```
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*Example*:
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#### force
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```haskell
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force :: NFData a => a -> a
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```
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*Example*:
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