Show HN: Common Lisp running natively over WebAssembly for the first time

[metagame]

A month or so ago, I ported a Common Lisp implementation (npt) to WebAssembly to make a silly blog post, because I was bored and have a lot of time on my hands to waste with things like this (I don't have a job, and because I have next to no experience, these meaningless, silly projects tend to fill what time I do have).

This is significant as it's the first time Common Lisp in particular has ever been hosted on it; wasm has a few poor decisions in its design that make it less-than-conducive to being a target for Common Lisp, and a lot of the more interesting implementations require an implementation to already be on the platform for bootstrapping purposes.

My previous attempts using other implementations haven't gone so well, despite throwing a lot of time at it (as an example, I have a fork of Eclipse Common Lisp, a defunct implementation from the 1990s, sitting on my disk with a few hundred lines of changes that I finally got to successfully compile and run a handful of very basic expressions, but it blows up when you try and define anything). In comparison, I was pleasantly surprised by how little I had to do, even though I did end up scrapping loads of lines of my own changes to npt in the process as I got a handle on how to make it work acceptably.

The Emscripten toolchain and I don't get along, partially because I don't like inlining ECMAScript into my C and vice-versa, so it's little more than a neat little demo right now.

You can load slightly more complex programs into it by hijacking the "imp" ECMAScript function every few hundred milliseconds with strings containing complete forms (this is essentially a batch processor, so there's no interactivity that allows it to wait while you decide what the rest of a form should be). Only one at a time, though. It's not that fancy.

If you mess up at all, even just a little error, it will crash. This is by design; I disabled the debugger. It's a giant hack, and the hack I eventually decided on left it impossible to have a debugging experience, with the benefit of getting to use a closer-to-unmodified npt.

This could be more useful, if I spent more time on it, but it's more fun if it's just a demo. I hope you enjoy the toy I made for you.

https://en.wikipedia.org/wiki/Batch_processing

If you don't know what forms are in the context of Common Lisp:

http://www.lispworks.com/documentation/HyperSpec/Body/03_aba...

http://www.lispworks.com/documentation/HyperSpec/Body/26_glo...

[aidenn0]

This probably doesn't count as "natively" but I've run ABCL[1] under Doppio[2]. Startup times are under a minute in Chromium based browsers and under an hour in Firefox. I've run into zero stability issues, but its no speed demon.

[edit]

Just tried again today and Firefox gets to a REPL in about 3.5 minutes, while chromium is still right about 1 minute.

1: https://abcl.org/

2: https://plasma-umass.org/doppio-demo/

[metagame]

Thank you for making it!

Unfortunately, a JVM on wasm would be quite difficult for the same reason that Lisp over wasm is quite difficult (I had actually looked for wasm JVMs before trying anything). I had no idea there was a JS JVM implementation! That's very cool.

[gumby]

Great work! You write,

> …wasm has a few poor decisions in its design that make it less-than-conducive to being a target for Common Lisp…

Could you say a bit more about those design decisions?

[miloignis]

Not OP, but as a fellow Lisp-on-wasm developer one problem is that the current release doesn't support tail call elimination. There's a proposal for it (a tail_call instruction), and Chrome has implemented it, but the Firefox/Spidermonkey team hasn't prioritized it, so it's sat for a couple years. At least two implementations (maybe two browser implementations? I don't recall) are needed for standardization, so things remain.

You know, I wonder how seriously I could be taken if I duck-taped a wasm-capable browser together out of Servo and Wasmtime to make a second implementation and push it forwards...

[moonchild]

I believe there are challenges related to nonlocal transfer of control, as well as multiple return values. More damningly, if I recall correctly, lisp implementors were consulted and their feedback ignored (just like apl implementors with .net, back in the latter's infancy).

[mbrock]

I think a major limitation is that a WebAssembly module can’t run dynamically generated code, which is a huge part of typical Common Lisp implementations.

[metagame]

Thanks for the only compliment in the thread! I appreciate it, especially given I've been such a fan of your writing and life for such a long time.

I think that the people who responded to you covered much of it, but you can find more by doing a web search for it. I'd find you links myself, but it's early in the morning and I'm a little tired.

[catchclose8919]

...god, my eyes ...why is everything CL plagued by such horrible design choices (hyperspec, Lisp-IDEs... all!) - why such ugly colors, ugly typography, bad contrasts, ugly logos, ugly diagrams, ugly supporting graphics?!

I know that even the language itself is kind of the opposite of "beautiful", but the way all docs, blogs, websites etc. look ...seriously, is this intended to scare away any aesthetically sensitive people? Programming languages are about aesthetics too, and Lisp at its core (not CL ofc) is absolutely beautiful!

[dang]

"Please don't complain about tangential annoyances—things like article or website formats, name collisions, or back-button breakage. They're too common to be interesting."

https://news.ycombinator.com/newsguidelines.html

Your comment particularly broke the Show HN guidelines:

https://news.ycombinator.com/showhn.html

[christophilus]

Oh, wow. I thought you were just another HN hater, but nope. I think my eyes are bleeding.

[emacsperson]

Its actually quite readable in eww, the emacs web browser :^)

[coryrc]

The hyperspec is copyrighted and licensed in a way where we can't change it at all. It's like the primary source to learn so impossible for anyone knowledgeable to clean-room reverse engineer a new one.

[jhgb]

> why such ugly colors, ugly typography, bad contrasts, ugly logos, ugly diagrams, ugly supporting graphics

What? It looks perfectly fine on my monochromatic Genera monitor!

Jokes aside, Firefox's reader view makes it only marginally more readable. I wonder if it took the author extra effort to make it look like that, and whether there's a better page sanifier than the reader view.

[sj4nz]

PureScript always sets the bar high for this in my mind, here's an example documentation page: https://pursuit.purescript.org/packages/purescript-effect/4....

[dtagames]

So true! Also, there are no decent UI frameworks for Lisp, so it's impossible to build a full stack app that looks good in a modern browser without adding a TS or JS web component layer. And... There's no modern IDE for Lisp.

I think this aspect of ignoring UIs and aesthetics has seriously held back CL.

[brokenkebab2]

Talking about the page behind the link - it's not like Sistine chapel, of course, but it's completely ok. In digital realm your perception is very strongly affected by medium/device/environment. Maybe that's the case. Not commenting about hyperspec though

[stareatgoats]

I think aesthetics is sometimes equated to "superficiality", "commerciality" even "girlishness" and the surface impression tends to be the polar opposite for niches that really want to distance themselves from anything such. Which is not commendable but there you go.

[hexo]

Still better than 3/4 of current web.

[mpfundstein]

i agree. its amazing. yhe hyperspec is unreadable anyway... never really helped me at all

[kotborealis]

Great work! A small nitpick — the page is a bit hard to read, links have low contrast, you can check it using accessibility tools.

[rsstack]

I initially rolled my eyes that it's yet another pointless text contrast complaint - and then I opened the site. My eye sight is great and that contrast (and border) is not great :)

[FraaJad]

So much complaint about color schemes. Hitting the Reader View formatted the page beautifully.

I'm thankful it is a simple HTML page that could be easily formatted using browser-built-in tools.

[ngcc_hk]

Is there something like a box that you can key in something and it works. Reader view give you text. Also that box?

I lost … perhaps I expect a REPL or … anyway not good to sell CL-webassembly I think.

[ngcc_hk]

Like reading Rfc in 1990s … a bit odd choice to use this format and font to sell anything these days.

[dang]

"Please don't complain about tangential annoyances—things like article or website formats, name collisions, or back-button breakage. They're too common to be interesting."

https://news.ycombinator.com/newsguidelines.html

[metagame]

Nothing's being sold; it's just a little toy.

[Existenceblinks]

I hope someone would create a tutorial which is using a toy programming language to compile to webassembly from scratch. Using existing language is too opaque to understand anything.

[metagame]

That sounds like a good idea. Have you considered writing it?