Avoid confusing with the built-in Map class. PR917

doc/handbook/Advanced Types.md

@@ -781,11 +781,11 @@ let unknown = getProperty(person, 'unknown'); // error, 'unknown' is not in 'nam
 并且`T[string]`为索引签名的类型：
 
 ```ts
-interface Map<T> {
+interface Dictionary<T> {
     [key: string]: T;
 }
-let keys: keyof Map<number>; // string
-let value: Map<number>['foo']; // number
+let keys: keyof Dictionary<number>; // string
+let value: Dictionary<number>['foo']; // number
 ```
 
 # 映射类型