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32 lines
761 B
32 lines
761 B
7 years ago
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# Chapter Exercises
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1. `length :: [a] -> Int` (Why not `Integer`?)
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2. Answers:
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1. 5
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2. 3
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3. 2
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4. 5
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3. `(/)` takes two `Fractional` types. `length` returns and `Int` which is not `Fractional`. (`Float` and `Double` are)
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4. Use `div` instead: `div 6 $ length [1, 2, 3]`
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5. `Bool`. `True` (Note: `(+)` has higher precedence)
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6. `Bool`. `False`
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7. Answers:
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1. Works. `Bool`. `True`
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2. Won't work. List needs to have elements of the same type.
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3. Works. `Int`. `5`
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4. Works. `Bool`. `False`
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5. Won't work. `(&&)` needs two `Bool`'s, `9` isn't one.
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8. see src/chapter4.hs
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9. see src/chapter4.hs
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10. see src/chapter4.hs
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## Correcting syntax
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see src/chapter4.hs
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## Match the function names to their types
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1. (c)
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2. (b)
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3. (a)
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4. (d)
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