[curiousgibbon]

I haven't read much of the book but find the early material defining complex numbers as a sum type that's either R R I or R I R where R is some type representing the reals and I is some sort of unit type with one inhabitant rather strange. As someone who knows a little math and a little Haskell, this example seems contrived, misleading and weird from both angles. Should I read on or give up?

[kisonecat]

It looks like the text uses the more natural R R a few pages later.

[curiousgibbon]

Yes, but I'm dubious of the value of a learning resource this indirect. I waded through about 5 versions of the complex numbers, each more natural than the last and gave up on the book because it didn't seem like any reason for the tumultuous journey though weird models of the complex numbers would be elucidated. I'm now trying to crowdsource motivation to continue.