const regex = /{IF\s*([^}]+)}([\s\S]+)(?:{\/?ELSE})([\s\S]+?){\/IF}/gim;
// Alternative syntax using RegExp constructor
// const regex = new RegExp('{IF\\s*([^}]+)}([\\s\\S]+)(?:{\\\/?ELSE})([\\s\\S]+?){\\\/IF}', 'gim')
const str = `{IF !isLoggedIn}
<a href="/sign-in/">Sign In</a>
{ELSE}
Welcome back, {>username}!<br />
{# students}
<li>{#>last_name}, {#>first_name}</li>
{/#}
{/IF}
{IF isLoggedIn}
Beta Testing...
{/IF}`;
// Reset `lastIndex` if this regex is defined globally
// regex.lastIndex = 0;
let m;
while ((m = regex.exec(str)) !== null) {
// This is necessary to avoid infinite loops with zero-width matches
if (m.index === regex.lastIndex) {
regex.lastIndex++;
}
// The result can be accessed through the `m`-variable.
m.forEach((match, groupIndex) => {
console.log(`Found match, group ${groupIndex}: ${match}`);
});
}
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for JavaScript, please visit: https://developer.mozilla.org/en/docs/Web/JavaScript/Guide/Regular_Expressions