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anc2020

What I'm arguing is that you can still think and write with an imperative style using the IO monad if you want, so I'm not sure what the issue is.

Edit: As an aside, I already know that "Monad" doesn't mean impure (having implemented an IO monad in my spare time to find out) and that was implied when I said "100% pure functional [...] like Haskell".

They are implemented purely, nonetheless they do allow side-effect (impure) programming.

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His issue is precisely with things like the IO monad. At least that's how I parse this sentence:

"what's often a tremendous puzzle in Erlang (or Haskell) turns into straightforward code in Python or Perl or even C." (http://prog21.dadgum.com/54.html)

In my limited experience, the type-checking constraints in haskell make programs using monads unnecessarily hard to change. I just assumed I didn't know what I was doing; it's interesting that James Hague is agreeing with a lot more knowledge and experience.

If you do it wrong, sure. If you use a newtype alias instead of the raw underlying type, it's very easy to change things around.

Good suggestion, thanks.

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