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All programming philosophies are about state

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Re: All programming philosophies are about state

#81

Post by vc8f6vVV »

ARandomerDude wrote: post #72
vc8f6vVV wrote: post #50

Earlier quoted context omitted.

Not really. Try to interact with DB in FP. Yes, there is a referential transparency ... when combining functions which call DB (e.g. using monads). As a result you get a composite function, which is the same every time you run that composition. Who cares really? When you execute that composite function though you will potentially get different results and your "referential transparency" goes out the window. Of course…

DB operations are not what is being described in the conversation about referential transparency. We’re talking about something that starts with things like reduce vs. a for loop with mutable variables to accumulate values. Once the language forces you to think in terms of stateful operations to perform even basic tasks, the reflexive tendency is to use mutable state to perform any task. At that point, nobody really…

But we do have loops in the real world, don't we? So in a true FP we are talking about recursion as an alternative to for loops. Can you easily reduce recursive function? If you can, I can as well "reduce" for loop. Otherwise we are talking about a paradigm without recursions and side effects.

Re: All programming philosophies are about state

#83

Post by sjm »

bcherny wrote: post #71
IngoBlechschmid wrote: post #38

Earlier quoted context omitted.

Out of curiosity, why former?

“He who is not a républicain at twenty compels one to doubt the generosity of his heart; but he who, after thirty, persists, compels one to doubt the soundness of his mind.”

I really dislike this quote. It always comes across like it's designed to ease greedy people of their guilt for moving to the right as they earn more money. To me, being sound of mind is wanting everyone to have what you have, or at least an equal shot of getting there from wherever they had the roll of the dice of being born.

Re: All programming philosophies are about state

#84

Post by bcherny »

sjm wrote: post #83
bcherny wrote: post #71

Earlier quoted context omitted.

“He who is not a républicain at twenty compels one to doubt the generosity of his heart; but he who, after thirty, persists, compels one to doubt the soundness of his mind.”

I really dislike this quote. It always comes across like it's designed to ease greedy people of their guilt for moving to the right as they earn more money. To me, being sound of mind is wanting everyone to have what you have, or at least an equal shot of getting there from wherever they had the roll of the dice of being born.

Not to agree or disagree with the quote itself, I’m simply giving a possible explanation for why the commenter may have changed their mind.

Re: All programming philosophies are about state

#85

Post by vore »

vc8f6vVV wrote: post #50
epgui wrote: post #9

Earlier quoted context omitted.

I think what you're missing is that functional programming is about referential transparency. There should be no need for an instruction pointer in your mental model.

Not really. Try to interact with DB in FP. Yes, there is a referential transparency ... when combining functions which call DB (e.g. using monads). As a result you get a composite function, which is the same every time you run that composition. Who cares really? When you execute that composite function though you will potentially get different results and your "referential transparency" goes out the window. Of course…

No, but this is why we have things like linear types or encapsulating side effects in a state monad to describe these kinds of strict sequencings. I personally think pure functional programming is still very unergonomic but referential transparency in the face of side effects is not an unsolved problem.

Besides, it's good practice to limit how widespread side effects are in any program, anyway.

Re: All programming philosophies are about state

#86

Post by bawolff »

paper_good wrote: post #77
bawolff wrote: post #70

Earlier quoted context omitted.

Disagreeing with someone's thesis is not the same as them making an error. Like maybe you don't find their argument compelling, but that's not the same as them making a factual error.

Since everyone already clearly understand what he means, so let's avoid playing semantics and instead focus on being clear and straightforward. It seems that your questions are only leading to more confusion and not offering any valuable perspectives.

My objection was i thought the original comment was being rude, not that it was hard to understand.

Re: All programming philosophies are about state

#88

Post by User23 »

epolanski wrote: post #39
chowells wrote: post #8

That doesn't really seem like a good summary of functional programming. It has state all over the place. But it's true that functional programming is about state management. I'd argue that the functional approach to state management is to make state explicit and visible.

FP is about evaluating expressions and it doesn't have state all over the place. I would also add that statefulness is incredibly hard and complex to get right in complex applications and pure fp languages like haskell lack enough emphasis on runtimes to handle this gracefully.

> FP is about evaluating expressions and it doesn't have state all over the place.

FP is all about side effects. Every time you declare something you're effecting a compile time side effect. And then there's monads, which are literally reinventing state with a worse API. I find it odd that no mainstream functional language has an explicit call stack monad and an explicit symbol table monad. Maybe because even the "purists" realize how asinine that would be.

> I would also add that statefulness is incredibly hard and complex to get right in complex applications and pure fp languages like haskell lack enough emphasis on runtimes to handle this gracefully.

Mutable state is a powerful tool. And it's true that if carpenters used table saws with the same level of discipline that programmers use compilers, there wouldn't be a carpenter left with any fingers.

Nevertheless, powerful tools can be used in a responsible and disciplined way and if you do you can be highly confident no unexpected dismemberment, literal or metaphorical, will occur.

Edit: to be more explicit, the mathematicians who invented Algol were well aware of all the theory for so-called functional programming and rejected it in favor of treating programs as transformations of a multidimensional space with good reason.

Re: All programming philosophies are about state

#89

Post by kortilla »

sjm wrote: post #83
bcherny wrote: post #71

Earlier quoted context omitted.

“He who is not a républicain at twenty compels one to doubt the generosity of his heart; but he who, after thirty, persists, compels one to doubt the soundness of his mind.”

I really dislike this quote. It always comes across like it's designed to ease greedy people of their guilt for moving to the right as they earn more money. To me, being sound of mind is wanting everyone to have what you have, or at least an equal shot of getting there from wherever they had the roll of the dice of being born.

Well sure, it’s “sound of mind” to you because that’s your political view.

To people on the right it’s just completely naive. The first half is mathematically impossible and the second half is so wishy washy that it leaves room for everyone to claim they were born further back in one aspect or another on the proverbial board.

Re: All programming philosophies are about state

#90

Post by philosopher1234 »

kortilla wrote: post #89
sjm wrote: post #83

Earlier quoted context omitted.

I really dislike this quote. It always comes across like it's designed to ease greedy people of their guilt for moving to the right as they earn more money. To me, being sound of mind is wanting everyone to have what you have, or at least an equal shot of getting there from wherever they had the roll of the dice of being born.

Well sure, it’s “sound of mind” to you because that’s your political view. To people on the right it’s just completely naive. The first half is mathematically impossible and the second half is so wishy washy that it leaves room for everyone to claim they were born further back in one aspect or another on the proverbial board.

> it leaves room for everyone to claim they were born further back in one aspect or another on the proverbial board.

Because generosity is exploitable, it's better to exploit.

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