Why can't I use question mark here, as it returns a Result?

help
1 
use anyhow::{Context as _, Result, anyhow};

fn main() {
    let closure = | x: i32 | -> anyhow::Result<()> {
        if x > 5 {
            return Err(anyhow!("bla"))
        } else {
            return Ok(())
        } 
    };
    
    let x = closure(9)?;
}

It won't compile, the error I get is "the ? operator can only be used in a function that returns Result or Option (or another type that implements FromResidual)", even tho the closure return type is Result!

2

Key word is "in". main doesn't return Result (you can add a return type so it returns Result).

2 Likes
3

you are absolutely right. haha. thank you.

4

... and the return type is ???

1 Like