63 lines
1.2 KiB
AppleScript
63 lines
1.2 KiB
AppleScript
-------------------- FIBONACCI SEQUENCE --------------------
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-- fib :: Int -> Int
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on fib(n)
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-- lastTwo : (Int, Int) -> (Int, Int)
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script lastTwo
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on |λ|([a, b])
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[b, a + b]
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end |λ|
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end script
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item 1 of foldl(lastTwo, {0, 1}, enumFromTo(1, n))
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end fib
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--------------------------- TEST ---------------------------
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on run
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fib(32)
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--> 2178309
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end run
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-------------------- GENERIC FUNCTIONS ---------------------
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-- enumFromTo :: Int -> Int -> [Int]
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on enumFromTo(m, n)
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if m ≤ n then
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set lst to {}
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repeat with i from m to n
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set end of lst to i
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end repeat
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lst
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else
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{}
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end if
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end enumFromTo
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-- foldl :: (a -> b -> a) -> a -> [b] -> a
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on foldl(f, startValue, xs)
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tell mReturn(f)
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set v to startValue
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set lng to length of xs
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repeat with i from 1 to lng
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set v to |λ|(v, item i of xs, i, xs)
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end repeat
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return v
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end tell
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end foldl
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-- Lift 2nd class handler function into 1st class script wrapper
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-- mReturn :: Handler -> Script
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on mReturn(f)
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if class of f is script then
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f
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else
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script
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property |λ| : f
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end script
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end if
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end mReturn
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