Rust expression order of evaluation

language design
27

What’s the current state regarding order of evaluation? It is very tempting to write this:

struct Item {
    a: u32,
    b: u32,
}

impl Item {
    fn receive_word(&mut self) -> Result<u32, Error> {
        …
    }

    fn receive(&mut self) -> Result<Item, Error> {
        Ok(Item {
            a: self.receive_word()?,
            b: self.receive_word()?,
        })
    }
}

The expectation is that first the value a is received, then the value b. But with a non-determinate evaluation order, one has to introduce temporaries.

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