向數組添加唯一對象

Question

我已經閱讀了關於Set的所有內容，並且它們不適合帳單，因爲我的對象不可哈希（這很常見）。

我有一個Product類

class Product: Object { 

    dynamic var sku: String! 
    dynamic var name: SomeUnhashableType! 
    dynamic var weight: String!  
} 

let uniqueProductArray = [productOne, productTwo, productThree] 

uniqueProductArray.append(productOne) 

我讀過有關使用contains，indexOf，filter等，但它們都使用謂詞，我想非謂語方法。

阻止重複對象被追加到數組的最優雅的方式是什麼？

Answer 1

通過將該協議添加到定義並通過爲您的課程實施==來爲您的課程Equatable。然後你可以使用contains不使用謂詞版本：

class Product: Object, Equatable { 
    dynamic var sku: String! 
    dynamic var name: String! 
    dynamic var weight: String! 
} 

func == (lhs: Product, rhs: Product) -> Bool { 
    return lhs.sku == rhs.sku && lhs.name == rhs.name && lhs.weight == rhs.weight 
} 

let productOne = Product() 
productOne.sku = "one" 
productOne.name = "name" 
productOne.weight = "heavy" 

let productTwo = Product() 
productTwo.sku = "two" 
productTwo.name = "name" 
productTwo.weight = "heavy" 

let productThree = Product() 
productThree.sku = "three" 
productThree.name = "name" 
productThree.weight = "heavy" 

var uniqueProductArray = [productOne, productTwo] 

if !uniqueProductArray.contains(productThree) { 
    uniqueProductArray.append(productThree) 
}