semver-trick VS avr-hal

Let's say crate B depends on crate A with a pinned dependency, and uses one of its types in a public interface.

Crate C depends on them both. It now can't bring in updates to A until B does, and when B updates that's a breaking change, so it better bump its major version.

Take a look at this teick, for example, for foundational crates updating their major version: https://github.com/dtolnay/semver-trick

Now imagine that being an issue every single patxh update.

Rust modules require a tiny bit more definition up-front, but they neatly decouple the module hierarchy from file layout so you can reorganize code however you like in future, and they support very fine grained control of privacy (such as being able to say pub(super) and pub(crate)). In extreme cases, you can even re-export symbols from one module in another without it counting as a breaking change, so you have even more options for evolving your project without breaking existing consumers. Look at the the semver trick as an example of how powerful this can be and how much freedom it gives library implementors. (And even if you're only a library consumer, wouldn't you rather be consuming libraries by implementors that had more freedom and power?)

A library author concerned about this can use the semver trick. TL;DR: if your current version is 0.42, you can do a 1.0 release, then do a 0.43 release that depends upon your 1.0 release and re-exports all the symbols.

I mean for all the parts of the standard library that do not change, one could presumably use the semver-trick.

The semver trick can help with libraries at least when they go to unify the ecosystem. Release new versions that replicate previous APIs in a compatible way while moving to the standard library implementation.

Because you still run into the problem that's been seen when various important crates upgraded and either didn't use the semver trick or had downstream crates specifying Cargo.toml version requirements too narrowly for it to be effective.

It's called the "semver-trick" [1].

[1]: https://github.com/dtolnay/semver-trick

The JVM is 114MiB on my machine. A near-minimal ggez program in debug mode is about 100MiB,¹ and ggez is small for a Rust application library. When you start getting into the 300s of dependencies (i.e. every time I've ever got beyond a trivial desktop application), you're lucky if your release build is less than 100MiB.

Sure, I could probably halve that by forking every dependency so they aren't duplicating versions, but that's a lot of work. (It's a shame Rust doesn't let you do conditional compilation based on dependency versions, or this would be a lot easier. As it is, we have to resort to the Semver trick: https://github.com/dtolnay/semver-trick/ — not that many people do that, so it's functionally useless.)

¹: I can get it down to around 8MiB with release mode, lto etc., but that significantly increases the build time and only about halves the weight of the intermediate build files.

/* * For examples (and inspiration), head to * * https://github.com/Rahix/avr-hal/tree/main/examples * * NOTE: Not all examples were ported to all boards! There is a good chance though, that code * for a different board can be adapted for yours. The Arduino Uno currently has the most * examples available. */ #![no_std] #![no_main] use dht_sensor::*; use panic_halt as _; #[arduino_hal::entry] fn main() -> ! { let dp = arduino_hal::Peripherals::take().unwrap(); let pins = arduino_hal::pins!(dp); let mut serial = arduino_hal::default_serial!(dp, pins, 57200); let mut pin3 = pins.d3.into_opendrain_high(); let mut delay = arduino_hal::Delay::new(); ufmt::uwriteln!(serial, "{}", "waiting for sensor...").unwrap(); arduino_hal::delay_ms(2000); loop { match dht11::Reading::read(&mut delay, &mut pin3) { Ok(dht11::Reading { temperature, relative_humidity, }) => ufmt::uwriteln!(serial, "{}°, {}% RH", temperature, relative_humidity).unwrap(), Err(_e) => ufmt::uwriteln!(serial, "Error {}", "Unable to read").unwrap(), } arduino_hal::delay_ms(2000); } }

I found the generics a lot less of a problem when I realized I could parametrize on things like embedded_hal::serial::Write instead of UsartOps https://github.com/Rahix/avr-hal/pull/264/commits/17ed15321cb8fcf8aedb1f8133be1f189eb06a6f

I've come across avr-rust, avr-hal and both seem to have arduino stuff, wondering which is the most beginner friendly? (I have a bit of experience with the regular arduino IDE but want to switch over to doing all the stuff in rust for a challenge)

fyi, a minor follow-up at https://github.com/Rahix/avr-hal/issues/388

I have contributed a little to this. avr-hal I have done a couple little hobby projects with it as well, but I can't say it's the best thing out there.

All you need is in the documentation: https://rahix.github.io/avr-hal/arduino_hal/index.html even though reading the documentation without knowing what you're looking for can be quite difficult, so looking at some examples might be more helpful.

Rust language shares all advantages of efficient C++ code. With the rust community growing year after year, more and more people try using rust to program their Arduino boards. Consequently, the Arduino Rust ecosystem have significantly developed in the last couple of years. The Hardware Abstraction Layer for AVR microcontrollers avr-hal, Rudino library and ravedude CLI utility to make Rust development for AVR microcontrollers easier are just a few examples of the solid foundation developed so far.

Today I was toying with the arduino again, making an attached LED matrix print awesome messages better than it previously had. I wanted to use millis() found in the examples in the unsurpassed avr-hal crate, to orchestrate the duration it should show (part of) a character before moving on. But that is all besides the point. I made a few mistakes that coincidentally compiled and as such made me believe I was doing things right. (Perhaps I should note here that I am visually impaired so it is a bit easier for me to glance over smaller differences.)

There's a blink example in the repo for the avr-hal crate.

I'm trying to make an Arduino display text on an LCD using I2C (HD44780). So far, I've used arduino-hal from the avr-hal crate (github.com/Rahix/avr-hal) to program the Arduino, and I wonder if anyone happens to know of a library/crate which is compatible with it? So far I've only found ag-lcd which doesn't seem to work with I2C.