// let age:number = 50
// let height:number = 175.5
// let isStudent:boolean = true
// let isOpen:boolean = false
// let name: string = "Alice"
// let greeting: string = 'Hello, TypeScript!';
// let score:number|null = null
// let description:string|undefined = undefined
// const symbol1 = Symbol("key1")
// const symbol2 = Symbol("key2")
// let value:any = 2
// value = "111"
// value = true
// function test(message: string): void {
// }
// function throwError(message: string): never {
// throw Error(message)
// }
// let person = {
// name : "John",
// age : 30,
// greet() {
// console.log("Hello, I'm" this.name);
// }
// }
let a:number[] = [1,2,3];
let b:Array<number> = [2,3,5];
let c:[number,string] = [5,"11"];
enum Color{
Red = 2,
Green,
Blue
}
let color:Color = Color.Red;
console.log(color)
let aunknown:unknown = 5;
function aa():void {
console.info("aa")
}
aa()
let undefinedvar:undefined = undefined;
let nullvar:null = null;
let unionvar: number|string = 5;
console.log("aunknown===unionvar:"+(aunknown===unionvar));
function test2(num:number, num2?:number) {
if(num2) {
console.log("num2:"+num2);
}else{
console.log("num:"+num);
}
}
test2(1,2);
test2(5);
function test3(...arr:number[]) {
for(let num of arr) {
console.log(num)
}
}
test3(1,55,6);
test3(25);