Beginners

Rust makes it very easy to express conditional compilation, especially thanks to Cargo “features”. They’re well integrated into the language and are very easy to use. But one thing I’ve learned by maintaining RSpotify (a library for the Spotify API) is that one shouldn’t obsess over them. Conditional compilation should be used when it’s the only way to solve the problem, for a number of reasons I’ll explain in this article. This might be obvious, but to me, it wasn’t so clear back when I started using Rust. Even if you’re already aware, it might be a good reminder — maybe you forgot about it in your latest project, and you added an unnecessary feature. ...

Optional or default parameters are a very interesting feature of some languages that Rust specifically doesn’t cover (and looks like it won’t anytime soon). Say your library has lots of endpoints like so: fn endpoint<T1, T2, T3, ...>(mandatory: T1, opt1: Option<T2>, opt2: Option<T3>, ...); In this case, when you call endpoint, you have to use endpoint(mandatory, None, None, ...), or endpoint(mandatory, Some(val1), Some(val2), ...), instead of the more intuitive endpoint(mandatory) or endpoint(mandatory, val1, val2). Other languages like Python have named arguments, which make optional parameters natural and easier to read: endpoint(mandatory, opt1=val1, opt2=val2), while also allowing them to be written in any order. ...