I don't know enough about rust to understand how this would operate during compile time w.r.t if a user tries to define a field named 'async'. Is that no longer allowed or would the compiler be able to disambiguate?
error[E0721]: `await` is a keyword in the 2018 edition
--> src/lib.rs:2:5
|
2 | await: i32
| ^^^^^ help: you can use a raw identifier to stay compatible: `r#await`
https://en.wikipedia.org/wiki/Reserved_word
> Not all languages have the same numbers of reserved words. For example, Java (and other C derivatives) has a rather sparse complement of reserved words—approximately 50 – whereas COBOL has approximately 400. At the other end of the spectrum, pure Prolog and PL/I have none at all.
I don't really know why modern programming languages bother with reserved words. Yes, it would be confusing to have a variable named 'if', but compared to all of the other ways to write confusing code in, say, C, that's barely a drop in the bucket. Plus, it's something good tooling (highlighting, for example) could obviate, as it's entirely possible to use a grammar to show exactly what role each token is playing in a statement.
Preventing potential footguns prevents a large number of bugs. In fact, preventing a specific kind of footgun is one of the primary reasons that Rust exists.
Fewer footguns means easier to work with code. Easy to work with code means fewer bugs. If having reserved words removes more footguns than it creates than they are a good thing to have - and IMO - they do indeed prevent confusion and footguns.
As long as these footguns can be removed without giving up much in exchange, I say remove all footguns!
I would speculate that both will be true. The compile could disambiguate, but it will not be allowed.