Text Processing with JavaScript

Recipe 25

Looking For Whole Words Only with the Word Boundary (\b)

Task

Say you want to look for the word “green” in a document. You try using the includes() method, but it matches other words containing “green” too, such as “greenhouse” and “evergreen”:

part_2/word_boundary/word_boundary_ex1.js

const str1 = "We must reduce the emissions of greenhouse gases.";
const str2 = "An evergreen plant has leaves for the whole year.";

str1.includes("green");    // → true
str2.includes("green");    // → true

Adding a space around “green” doesn’t quite cut it because the word might be followed by a comma, appear before/after a newline character, or come at the beginning/end of a sentence, and so on:

part_2/word_boundary/word_boundary_ex2.js ...