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Very much a rust newbie. What is this syntax called?

> inout(reg) a,

inout looks like a function but I don't see how that works with the `a` variable. Is this some magic specifically for asm!?

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This is specific to asm!. It is a macro, and you can use macros to implement custom syntactic constructs.

Thanks! I'll have to take a look at the Macros section of the book.

See also the documentation on inline assembly here: https://doc.rust-lang.org/nightly/reference/inline-assembly.... .

The Little Book of Rust Macros[0] is also worth a look imho, it helped me a lot when I started learning macros.

[0] https://veykril.github.io/tlborm/introduction.html

Thanks! Been using rust for a while now and macros seem to be kind of like the final Frontier of Rust development

I don't have any problems with macros but I still don't get traits & trait objects. The combination of weird syntax, error messages and unexpected limitations confuses me every time. I'm getting the impression that abstraction isn't quite my thing.

Luckily there's still enums. Not as flexible but they make sense to me and don't sprinkle annotation boilerplate everywhere.

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