Except Rust modules (which are the subject here) are anything but innovative, there are plenty of languages since Mesa, CLU and ML came to the world with equally or better module systems.

Who invented modules first is moot when you're picking the language to write your next project in. Just like who invented the assembly line is moot when you are shopping for your next car. "The bar" for a car isn't Ford because Henry Ford was innovative. People don't really care about any of that when evaluating their next choice.

So what has Rust brought into modules to set the bar that isn't already available in other systems programming languages, with exception of C and C++?

Ok, I am bit harsh here, but for me there ARE no other systems languages except C, C++ and recently maybe Rust. I am also told, that in distant lands with strange and foreign customs, Ada is a systems language. (I don't know - no Ada missionaries have yet set foot on our shares and preached it to us.)

>no Ada missionaries have yet set foot on our shares

I'm not sure if 'shares' is a typo or not, but it fits great with my impression of why companies choose the languages they do sometimes: everyone else uses it (it's the local culture/custom), and nothing/no one has forced them to change (by lowering their profits/share value).

It was a typo, should have been "shores". However, it was a brilliant typo - the powers that be have decided on Greenhill and ClearCase. And the people who decide these things seem to be closer to the share holders than they are to us coders, so Ada missionaries on shares is maybe what it takes.

A really damn good execution.

Which in my mind matters more than all this pedantry.

In what sense do Rust modules provide a better execution over Ada packages?

If we define "the bar" as "people's expectations for what a useable module system looks like" you can set it without being novel at all

Note that I didn't mention innovation or novelty or originality. I just said that Rust "set the bar." To respond to your objection I'd just clarify by qualifying it better and refer to the "systems programming" or whatever domain C/C++ and Rust both belong to.

So then check modules in Modula-2, Modula-2+, Modula-3, Ada, Oberon, Oberon-2, Oberon-07, Active Oberon, Component Pascal, Turbo Pascal.

All used in the context of systems programming.

Rust modules don't add anything new to them.

It adds an excellent packaging system and developer experience in the form of cargo, which is also a package manager for external modules. "The bar", I think, is taken to mean the combination of all of these features and their execution, not the idea of modules.

A packaging system is orthogonal to modules.

Those ideas are also present in Maven, Gradle, NuGet. All older than cargo.

And all trace back to CPAN as general concept.

I am still waiting for cargo to support binary libraries.

Rust has not brought much new in terms of modules. It just has decent modules support according to established best-practice. The innovations are primarily around the borrow-checker.

That I agree with.

There are plenty of widely-used languages that have modules and came well before rust.