JavaScr...ier::XS(3)

💖 JavaScript::Minifier::XS — the XS glow-up bestie edition 💖

okay so real talk: this is the manual page for JavaScript::Minifier::XS, section 3 of the manual. It's a JavaScript minifier, it's written in XS, and it is fast. Let's get into it. ✨

---

✨ SYNOPSIS ✨

use JavaScript::Minifier::XS qw(minify);
my $js       = '...';
my $minified = minify($js);

that's it. that's the whole vibe. 🎀

---

🌸 DESCRIPTION 🌸

JavaScript::Minifier::XS is a JavaScript "minifier". Its whole job is to strip out unnecessary whitespace and comments from JavaScript files without breaking the JavaScript. Not breaking it is, like, the entire point. 🫶

It's similar in function to JavaScript::Minifier, but it's substantially faster because it's written in XS and not just pure Perl. the way that it's XS and not Perl… it's giving speed. it's giving efficiency. 💅

---

🦋 METHODS 🦋

• minify($js) — Minifies the given $js, and hands the minified JavaScript right back to the caller. give it JS, get JS back, but smaller. slay. 👑

---

🌈 HOW IT WORKS 🌈

JavaScript::Minifier::XS minifies by removing unnecessary whitespace from JavaScript documents. Comments (both block and line) are also removed — except when:

1. they contain the word "copyright" in them, or
2. they're needed to implement "IE Conditional Compilation".

those two get to stay. everyone else, pack it up. 🙈

Internally, the minification process is done by taking multiple passes through the JavaScript document:

🌟 Pass 1: Tokenize 🌟

First, we go through and parse the JavaScript document into a series of tokens internally. Important: the tokenizing process does not check to make sure you've got syntactically valid JavaScript. It just breaks up the text into a stream of tokens suitable for processing by the subsequent stages. no vibe check on your syntax, bestie. it just tokenizes. 💀

🌟 Pass 2: Collapse 🌟

We then march through the token list and collapse certain tokens down to their smallest possible representation. If they're still included in the final results, we only want to include them at their shortest. main character energy: shortest possible representation, always. ✨

Whitespace

Runs of multiple whitespace characters are reduced down to a single whitespace character. If the whitespace contains any "end of line" (EOL) characters, then the end result is the first EOL character encountered. Otherwise, the result is the first whitespace character in the run.

tl;dr — a big blob of spaces becomes one thing. if there's an EOL in there, you get the first EOL. if not, you get the first whitespace char. no cap.

🌟 Pass 3: Pruning 🌟

We then go back through the token list and prune and remove unnecessary tokens.

Whitespace

Wherever possible, whitespace is removed: before+after comment blocks, and before+after various symbols/sigils. whitespace? never met her. 🧚

Comments

Comments that are either (a) IE conditional compilation comments, or that (b) contain the word "copyright" in them are preserved. All other comments (line and block) are removed. the copyright ones survive. iconic behavior honestly. 💖

Everything else

We keep everything else: identifiers, quoted literal strings, symbols/sigils, etc. leave those alone, they're doing great. 🌸

🌟 Pass 4: Re-assembly 🌟

Lastly, we go back through the token list and re-assemble it all back into a single JavaScript string, which is then returned back to the caller. put it back together, but smaller. the glow-down that is actually a glow-up. ⭐

---

👑 AUTHOR 👑

Graham TerMarsch (cpan@howlingfrog.com) shoutout to the author fr fr. 🫶

---

💜 COPYRIGHT 💜

Copyright (C) 2007-, Graham TerMarsch. All Rights Reserved.

This is free software; you can redistribute it and/or modify it under the same license as Perl itself. free software besties, same license as Perl, we love that for us. 💅

---

🍓 SEE ALSO 🍓

• JavaScript::Minifier — the pure-Perl cousin. same function, different font. ✨

---

and that's the whole page, bestie. no notes. periodt. 💖

this page came from perl v5.42.2, dated 2026-06-29, and it lives in section 3 of the manual as JavaScr...ier::XS(3) — aka JavaScript::Minifier::XS(3). go forth and minify. 🎀🦋