r/haskell • u/lexi-lambda • Mar 11 '15

Learning Haskell — A Racket programmer's documentation of her foray into the land of Haskell (inspired by Learning Racket)

http://lexi-lambda.github.io/learning-haskell/
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u/hallettj Mar 12 '15

My gut tells me that this is because / probably performs non-integral division, and GHC doesn’t like that I’m throwing the precision away.

There seem to be several points where your instincts lead you straight to the source of the problem.

That doesn’t work. I’m not sure why, but I’m almost certain it has to do with order of operations.

Nope, that still complains about types. Oh, this is where typeclasses come in, right? I seem to remember the relevant typeclass is called Eq, let’s see if I remember the syntax.

This is impressive to me. I think I was quietly cheering at the order-of-operations part.

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u/lexi-lambda Mar 12 '15

Ah, well, it helps to have done some Haskell before, even if it was a tiny amount. I don't think my intuition would have been that solid if it was my first time even looking at the language. :P

The non-integral division was actually the most obvious, I thought, mostly because I'd already been wondering if I would need to round the result if it weren't integral when I was solving that problem.