cargo-cacher VS rust-playground

I had my own full local mirror with https://github.com/ChrisMacNaughton/cargo-cacher a few years back (repeated downloads in docker builds -.-). Iirc, it was 43 GB. I should probably donate some money for doing that… (To who, actually? Mozilla? Rust foundation?)

We can also optimize this more (e.g. a simple optimization to be two words instead of three: https://play.rust-lang.org/?version=stable&mode=debug&editio.... Also allows opting `Send` and `Sync` out or using non-`'static` lifetimes), but this works as a baseline. The only disadvantage is that if called in a function with `#[track_caller]` this will report the location of the caller... But this is something I can live with.

I like Rust, but this isn't one of it's strong suits. The code in the article is what Rustfmt outputs (playground link below), so it's syntactically idiomatic.

https://play.rust-lang.org/?version=stable&mode=debug&editio...

A tool, allowing you to access the rust playground right in the terminal and retaining all the features available on the web version.

This is a breaking change too, as it can break type inference: https://play.rust-lang.org/?edition=2021&gist=8d528bcec2b92b...

At first I was thinking about how to create a package manager website for a custom programming language, looking at crates.io and npmjs.com. But then you also want to have a "try" feature, if this package manager is for a language, so then it's like "code sandboxes" like play.rust-lang.org and the robust codesandbox.io for JS/TS.

If you have a StackOverflow account, consider asking it there instead! StackOverflow shows up much higher in search results, so having your question there also helps future Rust users (be sure to give it the "Rust" tag for maximum visibility). Note that this site is very interested in question quality. I've been asked to read a RFC I authored once. If you want your code reviewed or review other's code, there's a codereview stackexchange, too. If you need to test your code, maybe the Rust playground is for you.

The compiler won't choke, but it will stop you from accessing the value.

It doesn't matter if you omit the `else` clause or not, the type system ensures that you can't access invalid values.

Here's a bit of an example based off of @Ygg2's code: https://play.rust-lang.org/?version=stable&mode=debug&editio...

https://play.rust-lang.org/?version=stable&mode=debug&editio...

So I tried this in Rust, when you use `.chars().count()`, it gives you that same useless 5 value. Should definitely be 1 in that case. One character, you press right or left once on the keyboard, etc.

> How would you write that, if the field access was spelled `self.foo`? The language wouldn't be able to tell that you're not just recursively calling the getter!

You can require parentheses for method calls put methods and fields in separate namespaces.

https://play.rust-lang.org/?version=stable&mode=debug&editio...

Elixir supports paren-free calls but the default linter and formatter won't let you use them except for a few whitelisted DSLs. I've never missed not having them.

aaand here it is in Rust ([repl](https://play.rust-lang.org/?version=stable&mode=debug&edition=2021&gist=a57f434765c313334c38ee8b6dedf5a4)): struct A; impl PartialEq for A { fn eq(&self, _other: &isize) -> bool { true } }