Arithmetic

[JD95]

Have some problems that outline the differences between the different number type classes and how to deal with conversions between the two

[agentultra]

I think the property tests for division and modulus need work to cover examples where the divisor is 0.

Or, alternatively, we restrict the test input:

describe "Problem 4" $
  it "should perform integer division" $
    property $ \(x :: Int, (Positive y)) ->
      P.division x y == (x `div` y)

[JD95]

That's a good point. Should we make an explicit note to not worry about the case when it's zero (they'd cover that with maybe later) and only test non zero divisors?

[agentultra]

@JD95 I think that's fair. Most languages introduce it early but gloss over it unfairly I think.

The only reason to keep it in there is if we want to introduce some kind of option-type like Maybe or Either early on.

Then again there's a good reason we could just introduce it later in a different problem set.