From c678d198e4e58d2002e1bb5fd8620e4aa8b4c170 Mon Sep 17 00:00:00 2001
From: xiaox0321 <xiaox0321@163.com>
Date: Wed, 4 Jan 2017 13:34:06 +0800
Subject: [PATCH] Update 23_Generics.md (#680)
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参考官方文档，修改一些语法上的问题
---
 source/chapter2/23_Generics.md | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/source/chapter2/23_Generics.md b/source/chapter2/23_Generics.md
index 2b0e982f..f45c5a49 100644
--- a/source/chapter2/23_Generics.md
+++ b/source/chapter2/23_Generics.md
@@ -185,7 +185,7 @@ struct IntStack {
 ```swift
 struct Stack<Element> {
     var items = [Element]()
-    mutating func push(item: Element) {
+    mutating func push(_ item: Element) {
         items.append(item)
     }
     mutating func pop() -> Element {
@@ -330,8 +330,8 @@ func findIndex<T>(of valueToFind: T, in array:[T]) -> Int? {
 任何 `Equatable` 类型都可以安全地使用在 `findIndex(of:in:)` 函数中，因为其保证支持等式操作符。为了说明这个事实，当你定义一个函数时，你可以定义一个 `Equatable` 类型约束作为类型参数定义的一部分：
 
 ```swift
-func findIndex<T: Equatable>(array: [T], _ valueToFind: T) -> Int? {
-    for (index, value) in array.enumerate() {
+func findIndex<T: Equatable>(of valueToFind: T, in array:[T]) -> Int? {
+    for (index, value) in array.enumerated() {
         if value == valueToFind {
             return index
         }
@@ -364,7 +364,7 @@ let stringIndex = findIndex(of: "Andrea", in: ["Mike", "Malcolm", "Andrea"])
 ```swift
 protocol Container {
     associatedtype ItemType
-    mutating func append(item: ItemType)
+    mutating func append(_ item: ItemType)
     var count: Int { get }
     subscript(i: Int) -> ItemType { get }
 }
@@ -390,7 +390,7 @@ protocol Container {
 struct IntStack: Container {
     // IntStack 的原始实现部分
     var items = [Int]()
-    mutating func push(item: Int) {
+    mutating func push(_ item: Int) {
         items.append(item)
     }
     mutating func pop() -> Int {
@@ -398,7 +398,7 @@ struct IntStack: Container {
     }
     // Container 协议的实现部分
     typealias ItemType = Int
-    mutating func append(item: Int) {
+    mutating func append(_ item: Int) {
         self.push(item)
     }
     var count: Int {
@@ -422,14 +422,14 @@ struct IntStack: Container {
 struct Stack<Element>: Container {
     // Stack<Element> 的原始实现部分
     var items = [Element]()
-    mutating func push(item: Element) {
+    mutating func push(_ item: Element) {
         items.append(item)
     }
     mutating func pop() -> Element {
         return items.removeLast()
     }
     // Container 协议的实现部分
-    mutating func append(item: Element) {
+    mutating func append(_ item: Element) {
         self.push(item)
     }
     var count: Int {