Text Processing with JavaScript

Recipe 38

Creating Lazy Quantifiers with the Question Mark

Task

Suppose your task is to write a script that reduces the size of HTML files by removing all comments. The syntax for an HTML comment is <!-- Comment -->. So, to accomplish this task, you might assume that you just need to remove the opening and closing brackets of the comment syntax and any characters that exist between them:

part_2/lazy_quantifiers/lazy_ex1.js

const re = /<!--.*-->/;
const str = "HTML comment: <!-- I'm a comment -->";

str.replace(re, "");    // → "HTML comment: "

Here, the full stop (.) matches any character (except for a line break), and the quantifier * tells the engine to do this zero or more times. This pattern works for a single-line comment. What ...