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OCaml: a Rust developer's first impressions

pthorpe92.github.io

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Re: OCaml: a Rust developer's first impressions

#71

Post by masklinn »

cmrdporcupine wrote: post #28
satvikpendem wrote: post #5

Earlier quoted context omitted.

Yes and no, Rust is ML inspired but it is still way too imperative and not as functional to be called a true ML. But yes, things like Result and Option types, do-notion via "?," at least for Results and Options, algebraic data types are all part of the appeal. There sadly are still no higher kinded types though, but that is a difficult problem to solve and most won't encounter such problems anyway in day-to-day codin…

The ? thing, didn't that get borrow from Swift, in fact?

No. For starters ? was introduced by C# 2.0 almost 10 years before Swift appeared so it would have been lifted from that if anything, but then Rust’s ? has completely different semantics than everyone else.

Re: OCaml: a Rust developer's first impressions

#72

Post by oconnor663 »

> heavy use of chained iterator methods in favor over traditional loops. This is one of the more intimidating hurdles for newcomers to [Rust], but after getting used to it, rarely will you see anyone write a for loop again.

I think this varies a lot from person to person. Rust includes syntactic sugar for imperative code (like `if let` and `let else`), and personally I prefer to use that when it's not too much trouble. I find it's pretty rare that I reach for map/and_then/etc.

Re: OCaml: a Rust developer's first impressions

#73

Post by hurril »

sintheta wrote: post #65

Can't comment on the comparison to Rust, but I recently spent quite some time learning OCaml, working through the excellent and freely available cs3110 course https://cs3110.github.io/textbook/cover.html ; I really really wanted to like the language... I agree w/ the submitted article about the heavy reliance on linked lists and recursion, but what disillusioned me from it is that after many weeks of study I discover…

After a few weeks, I am disappointed in not being an expert at $new_thing. $new_thing bad!

Re: OCaml: a Rust developer's first impressions

#74

Post by pjmlp »

vlovich123 wrote: post #43
debo_ wrote: post #15

Earlier quoted context omitted.

True. In this case the author is speaking specifically about OCaml, which is quite comfortable to write imperatively. I think the thing that tickles most people about Rust is the thoroughness of the type inference and type checking, which one generally gets from any ML.

Yeah but traditional ML languages are ass slow. If I want to write applications that are that slow, why not use something that targets the browser or something like Ruby or Python that has a much deeper ecosystem to leverage? Unless you’re just playing around with building a language and trying out different ideas or you think it’s better at some other axis (eg lower defect rate). But I’ve generally found that my inc…

As someone that was introduced into ML languages via Caml Light in 1995, and has used a few of them since then, if the program is ass slow maybe the developer should have spent some time reading and practicing Algorithms and Data Structures.

Re: OCaml: a Rust developer's first impressions

#75

Post by ReleaseCandidat »

>... linked lists are slow and inefficient with modern CPU caches, and you should almost never use them

You should not use them most of the time in functional languages (like OCaml and Haskell and...) for this reasons either, it's just that (almost) all examples for beginners use them because they are "easier" than for example trees.

Oh, by the way, OCaml does not have significant whitespace (but e.g.F# and Haskell do).

Re: OCaml: a Rust developer's first impressions

#76

Post by pjmlp »

whateveracct wrote: post #30
debo_ wrote: post #4

Earlier quoted context omitted.

I think about it the other way; Rust is an ML with a borrow checker. Most of the stuff I hear people gushing about in Rust is IMO them experiencing what's it's like to write ML.

ML with a borrow checker is a bit of an oxymoron though. Because proper closures (the kind Rust can't do) are essential for the classic functional programming that ML represents.

Nope, that is what an ML with linear types does.

Re: OCaml: a Rust developer's first impressions

#77

Post by hurril »

bananapub wrote: post #13
frodowtf wrote: post #10

Earlier quoted context omitted.

People say that OCaml is like Rust, but unlike Rust, OCaml has Exceptions that could appear everywhere. How is that safe?

why do feel exceptions make a language unsafe?

Safe isn't the best word to describe it with. But it does mean that any expression or statement always has two possible control flows. You have the "surface flow" as well as the exceptional flow, so there's an added complexity.

I never felt this was a problem when I did Java though (despite their awkwardness - basically forcing coders to not use checked exceptions.)

Rust's control flow syntax for Results and Options are very similar to this but with an added benefit: you don't have to use the ?-operator.

panics is different, however. They are more akin to the way any Java program will happily OutOfMemoryError or NoClassDefFoundError given circumstances not (always) in your control.

Re: OCaml: a Rust developer's first impressions

#78

Post by hurril »

hurril wrote: post #73
sintheta wrote: post #65

Can't comment on the comparison to Rust, but I recently spent quite some time learning OCaml, working through the excellent and freely available cs3110 course https://cs3110.github.io/textbook/cover.html ; I really really wanted to like the language... I agree w/ the submitted article about the heavy reliance on linked lists and recursion, but what disillusioned me from it is that after many weeks of study I discover…

After a few weeks, I am disappointed in not being an expert at $new_thing. $new_thing bad!

Downvote it all you want. I've spent the last decade writing in this style and to me it's second nature. Starting Rust I've had to basically relearn solving problems with loops and iterators. Solving problems with loops is not the way I think.

Never once thought negatively of Rust for this.

Re: OCaml: a Rust developer's first impressions

#79

Post by Jaxan »

ReleaseCandidat wrote: post #75

>... linked lists are slow and inefficient with modern CPU caches, and you should almost never use them You should not use them most of the time in functional languages (like OCaml and Haskell and...) for this reasons either, it's just that (almost) all examples for beginners use them because they are "easier" than for example trees. Oh, by the way, OCaml does not have significant whitespace (but e.g.F# and Haskell d…

In Haskell you typically don’t allocate any memory when using the default list type, because of laziness. The it’s totally fine and efficient. Just don’t use it to store data for later retrieval.

Re: OCaml: a Rust developer's first impressions

#80

Post by serial_dev »

hurril wrote: post #73
sintheta wrote: post #65

Can't comment on the comparison to Rust, but I recently spent quite some time learning OCaml, working through the excellent and freely available cs3110 course https://cs3110.github.io/textbook/cover.html ; I really really wanted to like the language... I agree w/ the submitted article about the heavy reliance on linked lists and recursion, but what disillusioned me from it is that after many weeks of study I discover…

After a few weeks, I am disappointed in not being an expert at $new_thing. $new_thing bad!

After a few weeks (and I believe it was written many weeks, so to me, that sounds like a couple of months), it's not unreasonable for experienced programmer with already a couple of languages in their toolbelt to expect to get _some_ things done in a new programming language.
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