GenericTree.swift

import Foundation

public class Tree<Element> {
    public var parent: Tree<Element>?
    public let value: Element
    public let children: [Tree<Element>]?
    
    init(withParent parent: Tree<Element>? = nil,value: Element,children: [Tree<Element>]? = nil) {
        self.parent = parent
        self.children = children
        self.value = value
        self.children?.forEach() { child in
            child.parent = self
        }
    }
    
    //MARK: - Utils
    
    public func isLeaf() -> Bool {
        return children == nil || children?.count == 0
    }
    
    public func isAnyChildrenLeaf() -> Bool {
        if let validChildren = children {
            for child in validChildren {
                if child.isLeaf() {
                    return true
                }
            }
        }
        return false
    }
}

public extension Tree where Element: Equatable {

    public func isParentOf(other: Tree?) -> Bool {
        if let parent = other?.parent?.value {
            return self.value == parent
        } else {
            return false
        }
    }
    
    public func isChildOf(other: Tree?) -> Bool {
        if let otherChildren = (other?.children?.map() { return $0.value }) {
            return otherChildren.find(self.value) != nil
        }
        return false
    }
}

public func ==<T: Equatable>(lhs: Tree<T>, rhs: Tree<T>) -> Bool {
    return lhs.value == rhs.value
}