This is a sample NPM module created in Learn Enough JavaScript to Be Dangerous by Michael Hartl.
The module can be used as follows:
$ npm install --global sambachimere-palindrome
$ vim test.js
let Phrase = require("sambachimere-palindrome");
let str = new Phrase("A man, a plan, a canal—Panama!");
console.log(str.palindrome());
\$ node test.js
true