The Rust module system is too confusing

Re:The Rust module system is too confusing by Thiez on Wednesday January 11, 2017 @05:44PM (#13378159)

I suppose it can get a little silly when you mix closures without arguments and the logical 'or' operator', e.g.:

    // prints 'true'
    println!("{}", true||(||true)()||(||true)());

Of course you wouldn't actually do this unless you're being intentionally obscure. Another favorite of mine:

    // prints '()'
    println!("{:?}", (||||||||||())()()()()());

But I can't recall ever running into such silly code, in practice the closure syntax and logical or do not lead to confusion (imho, ymmv).

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Re:The Rust module system is too confusing by MoSal on Wednesday January 11, 2017 @06:41PM (#13378537)

> in practice the closure syntax and logical or do not lead to confusion (imho, ymmv).

That's true. But put your self in the mind of a C developer looking at Rust code for the first time:

     if a || b {
       println!("True");
     }

Cool.

Then:

     thread::spawn(|| println!("Hello from a thread!"););

What? What is the logical or doing there?

----

IIRC, there are also cases where you have to write `& &` instead of `&&` to not confuse the compiler. That's a design/practical issue.

Both those issues would have been avoided if literal `and`/`or` were used.

I find it interesting how the only thing that momentarily confused me, as a C developer, about Rust syntax, was caused by Rust authors not wanting to syntactically deviate too much from C.

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