How to use `?` in a `.filter()` on an iterator.

result_from_iterator.rs

type Repository;

type Error;

trait X {
  fn is_needed(repo: &Repository) -> Result<bool, Error>
}

const ALL: [&dyn X; N] = [...];

let xs_or_error: Result<Vec<&dyn X>, Error> = ALL
    .iter()
    .map(|migration| -> Result<Option<&dyn Migrate>, OxenError> {
        if migration.is_needed(repo)? {
            Ok(Some(*migration))
        } else {
            Ok(None)
        }
    })
    .filter_map(|x| x.transpose())
    .collect();

let needed_xs: Vec<&dyn X> = x_or_error?;