Await Syntax Discussion Summary

language design
22

This is probably subjective, but the last example looks like a script to me, maybe a bit like Perl (which I don’t know much of, but to me represents a symbolful language).

Understanding the last example seems easier once you know what ? and # (maybe even knowing only one of them is enough to guess the other). But on the other hand, not knowing both seems to be the worst case here. Clearly ? is not the ternary operator and # is not a comment marker, but whatever they do affecting the control flow would be the most surprising to me. I think this is what the “weirdness budget” is.

On a prefix with no sugar syntax it could look like this:

async fn example(db: DB, hash: Sha256Hash) -> Result<String, Error> {
    let response = (await get("rust-lang.org"))?;
    let original_body = (await response.body)?
    let body = await add_footer(original_body);
    let db_operation = db.store_body_if_hash_eq(&body, hash)?;
    (await db_operation)?;
    body
}

Which is not worse IMO.

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