模組：外掛程式

例如，當您要使用延伸其他函式庫的 JavaScript 程式碼時。

ts
import { greeter } from "super-greeter";
// Normal Greeter API
greeter(2);
greeter("Hello world");
// Now we extend the object with a new function at runtime
import "hyper-super-greeter";
greeter.hyperGreet();

「super-greeter」的定義

ts
/*~ This example shows how to have multiple overloads for your function */
export interface GreeterFunction {
  (name: string): void
  (time: number): void
}
/*~ This example shows how to export a function specified by an interface */
export const greeter: GreeterFunction;

我們可以像以下這樣延伸現有模組

ts
// Type definitions for [~THE LIBRARY NAME~] [~OPTIONAL VERSION NUMBER~]
// Project: [~THE PROJECT NAME~]
// Definitions by: [~YOUR NAME~] <[~A URL FOR YOU~]>
/*~ This is the module plugin template file. You should rename it to index.d.ts
 *~ and place it in a folder with the same name as the module.
 *~ For example, if you were writing a file for "super-greeter", this
 *~ file should be 'super-greeter/index.d.ts'
 */
/*~ On this line, import the module which this module adds to */
import { greeter } from "super-greeter";
/*~ Here, declare the same module as the one you imported above
 *~ then we expand the existing declaration of the greeter function
 */
export module "super-greeter" {
  export interface GreeterFunction {
    /** Greets even better! */
    hyperGreet(): void;
  }
}

這使用 宣告合併

ES6 對模組外掛的影響

有些外掛會新增或修改現有模組的頂層匯出。雖然這在 CommonJS 和其他載入器中是合法的，但 ES6 模組被視為不可變的，因此這種模式將無法使用。由於 TypeScript 與載入器無關，因此不會在編譯時強制執行這項政策，但打算轉換到 ES6 模組載入器的開發人員應注意這一點。