命名空间和模块的区别

/// <reference path="path to namespace file"/>

export class Addition{
    constructor(private x?: number, private y?: number){
    }
    Sum(){
        console.log("SUM: " +(this.x + this.y));
    }
}

import {Addition} from './addition';
let addObject = new Addition(10, 20); 
addObject.Sum();

namespace invoiceCalc { 
   export namespace invoiceAccount { 
      export class Invoice { 
         public calculateDiscount(price: number) { 
            return price * .60; 
         } 
      } 
   } 
}

///<reference path="./StoreCalc.ts"/>
let invoice = new invoiceCalc.invoiceAccount.Invoice(); 
console.log("Output: "" +invoice.calculateDiscount(400));