Comment by CyberDildonics | Hacker News Reader

Comment by CyberDildonics | Hacker News Reader

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It sounds like like you're conflating pure and impure functions.

No I'm not, this applies to both in different ways.

If we're talking about pure functions, then due to referential transparency, arrays are in fact equivalent to functions

Never ever. You're talking about a function that generates data from an index, which is trivial to make. Just because it is possible to disguise it as an array in haskell, C++ or anything else doesn't mean it is a good idea. An array will have vastly different properties fundamentally and can be examined at any time because the data already exists.

Confusing the two is again conflating two things for no reason. Making a function that takes an index and returns something is a trivial interface, there is no value in trying to mix up the two.

Evidence of this can be found in the fact that you haven't tried to explain why this is a good idea, only that it works under haskell's semantics. Being clever with semantics is always possible, that doesn't mean conflating two things and hiding how things actually work is a good idea.

Notice that I never once in this discussion claimed that it was a "good idea". This is about research and experimentation. The blog post has the title because of the Haskell documentation. Also, claiming that the lack of an argument is evidence to the contrary is argument from silence, a logical fallacy.

The good idea surrounding this isn't about treating functions as data, but maintaining the purity of the type system allowing the implications of the type system to run their course. You seem to be a very pragmatic programmer and so the way Haskell builds up its own universe in terms of its own type system and Hask (the pseudo-category of Haskell objects) probably seems pointless to you. I can't say for certain, though.

I completely reject most of your claims because they appear to be incoherent within the framework of type theory and functional programming. It looks like you're using reasoning that applies only to procedural programming to attempt to prove why an idea in functional programming is bad.

This is about research and experimentation.

Haskell is 36 years old. It isn't research and experimentation any more, it is ideas that everyone with experience has had a look at. Some people might be learning haskell for the first time, but that doesn't mean it's still research, that all happened decades ago.

The good idea surrounding this isn't about treating functions as data, but maintaining the purity of the type system allowing the implications of the type system to run their course.

And what are the benefits here? How do they help the things I talked about? How do they avoid the pitfalls?

Also, claiming that the lack of an argument is evidence to the contrary is argument from silence, a logical fallacy.

Not really, because if you could contradict what I've said you would have.

within the framework of type theory and functional programming.

People can gather in a room and tell each other how great they are and how they have all the answers, but in 36 years there is a single email filtering program that was made with haskell.

you're using reasoning that applies only to procedural programming to attempt to prove why an idea in functional programming is bad.

I explained why this is a bad idea from fundamental and universally agreed upon ideas about the best ways to write software.

Functional programing languages had lots of ideas and features that turned out to work well. That doesn't mean that conflating two completely separate concepts is a good idea, no matter what 'type theory' someone comes up with to support it.

Saying something is good because haskell says it is good is circular religious thinking. These two things aren't the same, they are literally two different things and trying to unify them doesn't make life easier for anyone. It's just programming cleverness, like the 'goes to operator --> '

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