import Foundation extension Math { final class Overline: Atom { var innerList: AtomList? override var finalized: Math.Atom { let finalized = super.finalized if let overline = finalized as? Overline { overline.innerList = overline.innerList?.finalized } return finalized } init(_ overline: Overline) { self.innerList = overline.innerList.map { AtomList($0) } super.init(overline) } init(innerList: AtomList? = nil) { self.innerList = innerList super.init(type: .overline) } } }