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@gregpardo
Last active June 14, 2017 15:46
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Realm+CascadingDeletions
import Foundation
import RealmSwift
protocol CascadingDeletable {
var cascadingDeletions: [AnyObject?] { get }
}
extension Realm {
func delete<T: AnyObject>(cascading: List<T>) where T: CascadingDeletable {
let o = cascading
cascading.removeAll()
delete(o)
}
func delete<T: AnyObject>(cascading: Results<T>) where T: CascadingDeletable {
let o = cascading
delete(o)
}
func delete<T: AnyObject>(cascading: [T]) where T: CascadingDeletable {
for c in cascading {
delete(c as! Object)
}
}
func delete<T: AnyObject>(cascading: T) where T: Object, T: CascadingDeletable {
for child in cascading.cascadingDeletions {
if let object = child as? Object {
delete(object)
}
if let cascade = child as? CascadingDeletable {
delete(cascade as! Object)
}
}
delete(cascading)
}
}
@ndizazzo
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@AnthonyMDev - Realm provides initializers for an array of Realm Object<T>. The compiler can't infer the correct object type if you use .toArray().

func delete<T: AnyObject>(_ objects: List<T>, cascade: Bool = true) where T: CascadingDeletable {
    delete(Array(objects), cascade: cascade)
}

func delete<T: AnyObject>(_ objects: Results<T>, cascade: Bool = true) where T: CascadingDeletable {
    delete(Array(objects), cascade: cascade)
}

@Montrazul
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I tested this code today but it does not fullfill the requirements of a full cascading delete.

All my model classes are impelmenting the CascadingDeletable protocoll and are returning all childs that should be deleted in the cascadingDeletions array. Lets say you have the following structure:

Object A
   Sub 1
   Sub 2
      SubSub 2.1
      SubSub 2.2
   Sub 3
   ...

Sub 1, Sub 2, Sub 3 are getting deleted but SubSub 2.1, SubSub 2.2 and the Object A itself are not getting deleted with current Realm 2.4.0 version and your extensions. Tested on XCode 8 with Swift 3.0 and Realm 2.4.0.

@chrux
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chrux commented May 3, 2017

Same issue here, I haven't been able to remove the a List attribute.

@anfriis
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anfriis commented May 24, 2017

Any solutions to this?

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