Check out example codes for "npm typescript package". It will help you in understanding the concepts better.

Code Example 1

const demoMethod = () => {
return “I’m Duffer”;
module.exports = demoMethod;

Code Example 2

   "compilerOptions": {
       "target": "es5", /* Specify ECMAScript target version: 'ES3' (default), 'ES5', 'ES2015', 'ES2016', 'ES2017', 'ES2018', 'ES2019' or 'ESNEXT'. */
       "module": "commonjs",
       "allowJs": true, /* Allow javascript files to be compiled. */
       "strict": true, /* Enable all strict type-checking options. */
       "outDir": "./lib", /* Redirect output structure to the directory. */
       "esModuleInterop": true /* Enables emit interoperability between CommonJS and ES Modules via creation of namespace objects for all imports. Implies 'allowSyntheticDefaultImports'. */
   "include": ["src"],
   "exclude": ["node_modules"]

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