属性、方法以及继承

12 下标.playground/Contents.swift

@@ -0,0 +1,32 @@
+import Cocoa
+
+class Point {
+    var x = 0.0, y = 0.0
+    subscript(index: Int) -> Double {
+        set {
+            if index == 0 {
+                x = newValue
+            } else if index == 1 {
+                y = newValue
+            }
+        }
+        
+        get {
+            if index == 0 {
+                return x
+            } else if index == 1 {
+                return y
+            }
+            
+            return 0
+        }
+    }
+}
+
+var p = Point()
+p[0] = 11.1
+p[1] = 22.2
+print(p.x)
+print(p.y)
+print(p[0])
+print(p[1])