Make a struct iterable

[reenigneEsrever92]

Summary

Is it possible to make a struct iterable?

Additional Details

I want to define a struct in rust:

#[wasm_bindgen]
unsafe extern "C" {
    pub unsafe fn print(pos: Pos);
}

#[wasm_bindgen]
struct Pos {
    x: f64,
    y: f64
}

fn main() {
    print(Pos { x: 1.0, y: 2.0 });
}

so that if I pass it to js it can be iterated (implement Symbols.iterator method):

function print(pos) {
    for (const key in pos) {
        console.log(`${key}: ${pos[key]}`);
    }
}

prints:

x: 1
y: 2

[daxpedda]

This is not currently supported. See #1478 for workarounds. Also see #4142 for a proposal on how to address this.

Closing as duplicate of #1478.