fn area_of_effect(&self, torpedo_target: &Coord) -> CoordSet {
        torpedo_target
            .neighbors_with_diagonals()
            .into_iter()
            .filter(|coord| self.is_water(&coord))
            .chain(iter::once(torpedo_target.clone()))
            .collect()
    }
// water cells impacted by a torpedo fired at torpedo_target
water cells impacted by a torpedo fired at torpedo_target
water cells impacted by a torpedo fired at torpedo_target
fn area_of_effect(&self, torpedo_target: &Coord) -> CoordSet {
        torpedo_target
            .neighbors_with_diagonals()
            .into_iter()
            .filter(|coord| self.is_water(&coord))
            .chain(iter::once(torpedo_target.clone()))
            .collect()
    }
fn area_of_effect ( & self , torpedo_target : & Coord ) -> CoordSet { torpedo_target . neighbors_with_diagonals ( ) . into_iter ( ) . filter ( | coord | self . is_water ( & coord ) ) . chain ( iter :: once ( torpedo_target . clone ( ) ) ) . collect ( ) }
water cells impacted by a torpedo fired at torpedo_target
water cells impacted by a torpedo fired at torpedo_target
&self
torpedo_target
&Coord
&self
torpedo_target
&Coord