The avatar for @martien
Martien van Steenbergen
Wise Fool. Visioneer.
Published
Functional
Edited
Jan 16, 2021
1 fork
1 star
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//+ modulo :: Number -> Number -> Number
modulo = curry((divisor, dividend) => dividend % divisor)
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isOdd = modulo(2)
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isOdd(6)
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isOdd(5)
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//+ filter :: (a -> Bool) -> [a] -> [a]
filter = curry((f, xs) => xs.filter(f))
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filter(isOdd, [1,2,3,4,5,6,7,8,9])
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whatAreTheOdds = filter(isOdd)
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whatAreTheOdds([1,2,3,4,5,6,7,8,9])
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firstN = curry((n, word) => word.substring(0, n))
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first2 = firstN(2)
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first2("Hello")
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firstTwoLetters = map(first2)
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firstTwoLetters(["jim", "kate"])
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//+ first :: n -> [a] -> [a]
first = curry((n, array) => array.slice(0, n))
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//+ first2 :: [a] -> [a]
firstTwo = first(2)
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//+ firstTwoLetters2 :: [[a]] -> [[a]]
firstTwoLetters2 = map(firstTwo) // more concise than: _.map(words, word => firstN(word, 2))
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firstTwoLetters2(["jim", "kate"])
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map(firstTwo, ["jim", "katy"])
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