Hacker News Reader

Comment by czei002 | Hacker News Reader

Totally agree, macros are the worst Rust feature for me, they are way too powerful and break the tooling, e.g. fmt or language server.

https://rust-analyzer.github.io/blog/2021/11/21/ides-and-mac...

View on HN

It ultimately depends on how they're written. println! is a macro, and doesn't "break the tooling". on the other end of the spectrum, using a crate like demonstrate (unit testing) produces hard to understand errors and slows down the IDE.

I don't remember experiencing Rust Analyzer crashes for a long time, though (I do remember some in the past).

println! is only a declarative macro, whereas Maud is a proc macro.

The declarative macros aren't too head-twisting for tools, they just expand as declared, this can sometimes have a few surprising effects but generally it is very manageable. Procedural macros have essentially unlimited power and thus are sometimes entirely impossible to analyse.

println! depends on a proc macro: https://doc.rust-lang.org/stable/src/core/macros/mod.rs.html...

I see a built-in there. Are you really seeing a proc macro?

> println! is a macro, and doesn't "break the tooling"

I like, use, and write macros, but this isn't fully true. For example, recent Rust versions allow writing identifiers directly in the format string:

    println!("{some_identifier}")

However, this breaks rust-analyzer's ability to rename variables [1].

[1]: https://github.com/rust-lang/rust-analyzer/issues/11260#

Reply on news.ycombinator.com