I was trying to quickly drop some test results in a file for verification and ended up wanting to use the "?" operator in a scope. For instance:

struct MyErr {}

fn plop() -> Result<i32, MyErr> {
    Ok(42)
}
fn plap() -> Result<i32, MyErr> {
    Ok(43)
}

fn main() {
    let a: Result<i32, MyErr> = {
        Ok(plop()? + plap()?)
    };
    
    println!("{:?}", a);
}

which for me "should work" in the sense that my scope return a value, thus this value can be a result, the result type are compatible, etc.. but I get this error:

error[E0277]: the `?` operator can only be used in a function that returns `Result` or `Option` (or another type that implements `FromResidual`)
  --> src/main.rs:12:18
   |
10 | fn main() {
   | --------- this function should return `Result` or `Option` to accept `?`
11 |     let a: Result<i32, MyErr> = {
12 |         Ok(plop()? + plap()?)
   |                  ^ cannot use the `?` operator in a function that returns `()`
   |
help: consider adding return type
   |
10 ~ fn main() -> Result<(), Box<dyn std::error::Error>> {
11 |     let a: Result<i32, MyErr> = {
...
15 |     println!("{:?}", a);
16 +     Ok(())

where it seems that the "?" is catched by the main method instead of the scope. Is this normal or a bug ? Found it a bit confusing that the scope did not catch this operator.

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