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Rust--: Rust without the borrow checker

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Re: Rust--: Rust without the borrow checker

#131

Post by CodeMage »

corrode2711 wrote: post #110

I'm the author of this repo. I see some really angry comments, some of them even personal. Obviously I didn't think that just by tinkering with a compiler, I'd get personally attacked, but anyway, fair enough. For those of you confused: yes, this started as a satirical project with the corroded lib. Then I thought "why not just remove the borrow checker?" without any real motivation. Then I just went ahead and did it…

> Then I thought "why not just remove the borrow checker?" without any real motivation.

Reminds me of a chemistry kit I had as a kid. None of this tame, safe stuff you can buy these days. Mine was a gift from my dad and I never thought of asking him where he dug it up, but it had stuff like pure sulfuric acid in it.

One day, when I was done with all of the experiments I had planned to do, I decided to mix a few things and heat them up, just for fun, without any real motivation other than "let's see what happens".

Let's just say I was lucky we only had to replace some of the clothes my mom had left out for me to put away. ;)

> Another point is, as you guys are well aware, the borrow checker will reject some valid programs in order to never pass any invalid program. What if I'm sure about what I'm doing and I don't want that check to run?

Then you do it using the "unsafe" keyword, and you think long and hard about how to design and structure the code so that the unsafe code is small in scope, surface, and blast radius.

That's precisely what unsafe code is for: to get around the borrow checker and assert you know what you're doing. Of course, if you're wrong, that means your program will blow up, but at least you know that the culprit is hiding in one of those unsafe areas, rather than literally anywhere in the whole codebase.

Alternately, you can switch to a language with a different ethos.

The ethos of Rust is caring for memory safety so much that you willingly limit yourself in terms of what kind of code you write and you only step out of those limits reluctantly and with great care. That's something that resonates with a lot of people and Rust has been built on top of that for years.

If you suddenly take the product of those years of hard work, strip out the foundation it has been built on, and unironically offer it as a good idea, a lot of people won't like it and will tell you so. Mind, I'm not excusing the personal attacks, I'm just explaining the reaction.

Re: Rust--: Rust without the borrow checker

#133

Post by idontsee »

shmerl wrote: post #132

Isn't unsafe just for that? Why does it need a separate compiler?

The borrow checker still applies in unsafe { } blocks. What it means (iirc) is that you can do pointer/memory stuff that would otherwise not be allowed. But you still fully adhere to Rust semantics

Re: Rust--: Rust without the borrow checker

#134

Post by tempodox »

lordgroff wrote: post #123
tialaramex wrote: post #37

Earlier quoted context omitted.

If you write correct Rust code it'll work, the borrowck is just that, a check, if the teacher doesn't check your homework where you wrote that 10 + 5 = 15 it's still correct. If you write incorrect code where you break Rust's borrowing rules it'll have unbounded Undefined Behaviour, unlike the actual Rust where that'd be an error this thing will just give you broken garbage, exactly like a C++ compiler. Evidently mil…

The attitude expressed here and that tends to surface in any Rust discussion is the reason I completely lost interest in the language.

You’re expressing the same attitude here, just in reverse. Some users not thinking highly of C++ doesn’t make Rust a worse or less interesting language.

Re: Rust--: Rust without the borrow checker

#135

Post by indigoabstract »

MangoToupe wrote: post #129
indigoabstract wrote: post #114

My controversial opinion: If Rust were to "borrow" something from the C/C++ spirit, then disabling the borrow checker should be available as a compiler option. As in, you're an adult: if you want it, you can have it, instead of "we know better".

Is rust simple aesthetics to you? Why use rust, or any language at all really, at all then? The whole point of formal languages is to point a gun at the people who refuse to be adults. If we can't have this, C itself offers zero benefit over assembly.

I think it's more in the spirit of playfulness, like in "don't take yourself too seriously". It's why people want to mod Minecraft and Doom for example.

Because it's fun.

I can totally understand why you wouldn't want to do this though - the plethora of incompatible lisp dialects come to mind. That's why I said it was controversial.

Re: Rust--: Rust without the borrow checker

#137

Post by gpm »

qsera wrote: post #102
eru wrote: post #54

Earlier quoted context omitted.

Straightjackets can be very useful. Haskell (and OCaml etc) give you both straightjackets and a garbage collector. Straightjackets and GC are very compatible. Compared to C, which has neither straightjackets nor a GC (at least not by default).

>Haskell (and OCaml etc) give you both straightjackets.. Haskell's thing with purity and IO does not feel like that. In fact Haskell does it right (IO type is reflected in type). And rust messed it up ("safety" does not show up in types). You want a global mutable thing in Haskell? just use something like an `IORef` and that is it. It does not involve any complicated type magic. But mutations to it will only happen i…

> "safety" does not show up in types

It does in rust. An `unsafe fn()` is a different type than a (implicitly safe by the lack of keyword) `fn()`.

The difference is that unsafe fn's can be encapsulated in safe wrappers, where as IO functions sort of fundamentally can't be encapsulated in non-IO wrappers. This makes the IO tagged type signatures viral throughout your program (and as a result annoying), while the safety tagged type signatures are things you only have to think about if you're touching the non-encapsulated unsafe code yourself.

Re: Rust--: Rust without the borrow checker

#138

Post by elbear »

qsera wrote: post #102
eru wrote: post #54

Earlier quoted context omitted.

Straightjackets can be very useful. Haskell (and OCaml etc) give you both straightjackets and a garbage collector. Straightjackets and GC are very compatible. Compared to C, which has neither straightjackets nor a GC (at least not by default).

>Haskell (and OCaml etc) give you both straightjackets.. Haskell's thing with purity and IO does not feel like that. In fact Haskell does it right (IO type is reflected in type). And rust messed it up ("safety" does not show up in types). You want a global mutable thing in Haskell? just use something like an `IORef` and that is it. It does not involve any complicated type magic. But mutations to it will only happen i…

When I started learning Haskell, it did feel like coding with a straightjacket.

Re: Rust--: Rust without the borrow checker

#139

Post by ada0000 »

lordgroff wrote: post #126
ada0000 wrote: post #107

Earlier quoted context omitted.

herb sutter and the c++ community as a whole have put a lot of energy into improving the language and reducing UB; this has been a primary focus of C++26. they are not encouraging people to “churn out more broken garbage”, they are encouraging people to write better code in the language they have spent years developing libraries and expertise in.

And for which there's often no serious alternative to in many domains anyway.

even when there are alternatives, sometimes it makes sense to use a library like Qt in its native language with its native documentation rather than a binding - if you can do so safely

Re: Rust--: Rust without the borrow checker

#140

Post by npalli »

corrode2711 wrote: post #110

I'm the author of this repo. I see some really angry comments, some of them even personal. Obviously I didn't think that just by tinkering with a compiler, I'd get personally attacked, but anyway, fair enough. For those of you confused: yes, this started as a satirical project with the corroded lib. Then I thought "why not just remove the borrow checker?" without any real motivation. Then I just went ahead and did it…

You just need to master one package managed in depth and you will get what you really want with Modern C++.
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