泛型编程优化

Change-Id: I9277a3d20d4ce6d223c2f65067a481573a01a7f4

swiftdemo/swift01/swift01/JSONPlaceholder.swift

@@ -37,10 +37,18 @@ extension JSONPlaceholder : Decodable {
 }
 
 extension JSONPlaceholder {
-    static let all = Resource<[JSONPlaceholder]>(JSONPlaceholder.url!) {
-        (data) -> [JSONPlaceholder]? in
-        let posts = try? JSONDecoder().decode([JSONPlaceholder].self, from: data)
-        return posts
-        
-    }
+//    static let all = Resource<[JSONPlaceholder]>(JSONPlaceholder.url!) {
+//        (data) -> [JSONPlaceholder]? in
+//        let posts = try? JSONDecoder().decode([JSONPlaceholder].self, from: data)
+//        return posts
+//
+//    }
+    
+//    static let all = Resource<[JSONPlaceholder]>(url:JSONPlaceholder.url!) {
+//        (data) -> [JSONPlaceholder]? in
+//        return Resource.commonParse(data);
+//    }
+    
+    static let all = Resource<[JSONPlaceholder]>(url:JSONPlaceholder.url!,parse:Resource.commonParse)
+    
 }

swiftdemo/swift01/swift01/Resource.swift

@@ -11,17 +11,28 @@ import Foundation
 struct Resource<T> {
     let url: URL
     let parse: (Data) -> T?
+    
+
 }
 
 extension Resource where T: Decodable {
-    init(_ url: URL, parseJSON: @escaping (Data) -> T?) {
-        self.url = url
-//        self.parse = { data in
-//            let decoder = JSONDecoder()
-//            let object = try? decoder.decode(T.self, from: data)
-//            return object
-//        }
-        self.parse = parseJSON
+//    init(_ url: URL, parseJSON: @escaping (Data) -> T?) {
+//        self.url = url
+////        self.parse = { data in
+////            let decoder = JSONDecoder()
+////            let object = try? decoder.decode(T.self, from: data)
+////            return object
+////        }
+//        self.parse = parseJSON
+//        
+//
+//    }
+    
+    static func commonParse(_ data:Data) -> T? {
+        let decoder = JSONDecoder()
+        let object = try? decoder.decode(T.self, from: data)
+        return object
     }
+
 }