pub(crate) fn physics_of(
domains: &mut Domains,
r4: DomainHandle<EuclideanR4>,
) -> Result<&mut Physics<EuclideanR4>, Rejection>pub(crate) fn physics_of(
domains: &mut Domains,
r4: DomainHandle<EuclideanR4>,
) -> Result<&mut Physics<EuclideanR4>, Rejection>