Module Examples

A module in Node.js is a self-contained unit of code that exports functions or objects for other code to consume. It helps in organizing and reusing code, and in encapsulating implementation details.

Here's an example of a simple Node.js module that exports a function to calculate the sum of two numbers:

// myModule.js

exports.sum = function(a, b) {
    return a + b;
};

And here's how to use the module in another file:

// app.js

var myModule = require('./myModule');
var result = myModule.sum(1, 2);
console.log(result); // Outputs: 3

Here's an example of a simple Node.js module that exports a function that returns a Promise:

// myModule.js

exports.asyncSum = function(a, b) {
    return new Promise((resolve, reject) => {
        setTimeout(() => {
            if (a > b) {
              resolve(`${a} is greater than ${b}`);
            } else {
              reject(`${a} is less than ${b}`);
            }
        }, 1000);
    });
};

And here's how to use the module and handle the returned Promise in another file:

// app.js

var myModule = require('./myModule');

myModule.asyncSum(3, 2)
    .then(result => {
        console.log(result); // Outputs: 3 is greater than 2
    })
    .catch(error => {
        console.error(error);
    });