         op.build(for: self)
     }
 }
-
-/// A token type that has a package-private initializer to ensure that no other type other than PTypedColumn can confirm to PColumn
-public struct _PTypedColumnToken {
-    fileprivate init() {}
-}


    // A "poor-man's" equality check (without breaking PColumn as an existential
    func _isEqual(to box: PColumnBox) -> Bool

    // Ensure no one else can conform to PColumn other than PTypedColumn. This is to ensure
    // equality behaves in a reasonable manner, due to having to work around Swift's
    // existential type implementation.
    var _doNotConformToPColumn: _PTypedColumnToken { get }
}

fileprivate struct PColumnBoxImpl<T: ElementRequirements>: PColumnBox, Equatable {

        let rhsC = box as! PColumnBoxImpl<T>
        return self == rhsC
    }
}

fileprivate protocol HasNumeric {
