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Expand file tree Collapse file tree Original file line number Diff line number Diff line change @@ -18,5 +18,5 @@ program
1818 . parse ( process . argv )
1919
2020// 获取输入参数
21- console . log ( program . classroom ) ;
21+ console . log ( program . opts ( ) . classroom ) ;
2222
Original file line number Diff line number Diff line change @@ -17,4 +17,5 @@ $ npm link
17173 . 使用命令
1818```
1919$ csxiaoyao add
20+ $ csxiaoyao-add
2021```
Original file line number Diff line number Diff line change @@ -36,12 +36,15 @@ s = d as string; // 变量 as 类型
3636s = < string > d ; // <类型>变量
3737
3838// void
39- function fn ( ) : void { }
39+ function fn ( ) : void { } // 返回 null / undefined
4040
4141// never 表示永远不会返回结果
4242function fn2 ( ) : never {
4343 throw new Error ( '报错,立即结束,无返回值' ) ;
4444}
45+ function infiniteLoop ( ) : never { // 返回never的函数必须存在无法达到的终点
46+ while ( true ) { }
47+ }
4548
4649// object
4750let e : object ;
@@ -61,9 +64,13 @@ g = function(n1: number, n2: number): number {
6164let h : string [ ] ;
6265let i : Array < number > ;
6366
64- // tuple 元组,固定长度数组
67+ // tuple 元组,固定长度和类型的数组,各元素的类型不必相同
6568let j : [ string , number ] ;
6669j = [ 'hello' , 0 ] ;
70+ // 当访问一个越界的元素,会使用联合类型替代
71+ // j[3] = 'world'; // OK, 字符串可以赋值给(string | number)类型
72+ // console.log(j[5].toString()); // OK, 'string' 和 'number' 都有 toString
73+ // j[6] = true; // Error, 布尔不是(string | number)类型
6774
6875// enum 枚举
6976/*
7380 gender: 0,
7481}
7582console.log(k.gender === 0);*/
83+ enum Color { Red = 1 , Green , Blue }
84+ let ccc : Color = Color . Green ;
85+ let colorName : string = Color [ 1 ] ; // 显示'Red'因为上面代码里它的值是1
86+
7687enum Gender {
7788 Male = 0 ,
7889 Female = 1 ,
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