Plwm – An X11 window manager written in Prolog

by jedeusus • 1 year ago

225 64 1 year ago

Very nice. If you’re used to dwm this should be natural. Unless you use dwm’s tags as more than workspaces, which I do. The author does not, so he implemented workspaces instead of tags. So this can not replace dwm for me.

ninjin• 1 year ago

Tags are indeed a wonderful idea once it clicks, but I have to admit it took me about a year to get somewhat comfortable with how to work with them.

B1FF_PSUVM• 1 year ago

Why am I reminded of the all-Erlang HN first page?

pona-a2• 1 year ago

Fun fact: the first version of Erlang interpreter was written in Prolog.

YeGoblynQueenne• 1 year ago

Oh wow, I gotta try this.

Lots of documentation! Awesome!

rclkrtrzckr• 1 year ago

Isn't ".pl" actually used for perl?

Well, there might be a Prolog interpreter written in (a) perl (regex) ...

ajdude• 1 year ago

Prolog was using .pl for a bit over a decade before Perl existed.

jimjimjim• 1 year ago

Prolog is a older than Perl and there doesn't need to be any exclusive claim on file extensions.

tikhonj• 1 year ago

It's used for both which consistently confuses logic that guess programming language purely based on file extensions.

userbinator• 1 year ago

My first thought upon reading your comment was "it's used for Poland" ;-)

thijsvandien• 1 year ago

Then using .prl in stead wouldn’t have helped much…

gatane• 1 year ago

Time to do one in Scheme, I guess.

pona-a2• 1 year ago

Here's one in Guile Scheme.

https://wingolog.org/archives/2008/07/31/introducing-griddy

tmtvl• 1 year ago

Already exists: https://github.com/mwitmer/guile-wm

There might also be ones in other Schemes, but as FFI hasn't been standardised across Schemes yet I doubt there's an implementation-agnostic one.

mhd• 1 year ago

Done a while ago: https://en.wikipedia.org/wiki/Scwm

There was also "GWM", based on its own lisp dialect, "WOOL", which was around from at least the early 90s.

On the more popular side, you had sawfish (using an elisp-alike, IIRC) and stumpwm (Common Lisp).

anthk3• 1 year ago

Sawfish (the oficial VM of Gnome for a while) had Lisp plugins (or was it written in Lisp too?)

DonHopkins2• 1 year ago

Here's an X11 window manager, with pie menus and tabbed windows, entirely written in object oriented NeWS PostScript, from around 1991:

https://donhopkins.com/home/archive/NeWS/owm.ps.txt

And some design notes and emails on that NeWS based window manager for X11 windows:

https://donhopkins.com/home/archive/NeWS/i39l.txt

It incorporated NeWS tabbed windows written in PostScript, which could wrap around X11 windows (and frame NeWS windows too of course):

https://donhopkins.com/home/archive/NeWS/win/tab.ps

And NeWS pie menus written in PostScript, which you could pop up on tabbed window frames and manage X11 windows (and use in NeWS apps too of course):

https://donhopkins.com/home/archive/NeWS/win/pie.ps

There was also a virtual large scrolling desktop, and virtual multi-screen "rooms", both purely written in PostScript, which all plugged together with the tabbed windows and pie menus and X window manager seamlessly. They were all independent of each other and could be used separately, but worked together synergistically. Take that, ICCCM! ;)

Also here's a (pre-ICCCM, pre-X11) X10 window manager with pie menus, written in C and scripted in Forth, from around 1986:

https://donhopkins.com/home/archive/piemenu/uwm/fuwm-main.f

And some of my thoughts on X-Windows and ICCCM window management in general:

https://donhopkins.medium.com/the-x-windows-disaster-128d398...

In summary, ICCCM is a technological disaster: a toxic waste dump of broken protocols, backward compatibility nightmares, complex nonsolutions to obsolete nonproblems, a twisted mass of scabs and scar tissue intended to cover up the moral and intellectual depravity of the industry’s standard naked emperor.
Using these toolkits is like trying to make a bookshelf out of mashed potatoes." -Jamie Zawinski

agumonkey• 1 year ago

First time I ever get the chance to see object postcript/forth, thank you

igorhvr• 1 year ago

This one is customizable in Lisp, and overall pretty neat: https://sawfish.tuxfamily.org/ - I have been happily using it daily for many years now. :-)

eikenberry3• 1 year ago

I'm hoping one day someone will write a window-manager service for Wayland that replaces the compositor API with a protocol. To once again enable window managers to be implemented in any language, regardless of it having a Wayland/compositor library.

pyinstallwoes• 1 year ago

I wish more things were protocols instead of APIs.

linux26472• 1 year ago

Could you explain the difference?

PeakKS• 1 year ago

What? Wayland is a protocol. Not an API.

quotemstr• 1 year ago

The OP wants to decouple the compositor from the window manager and have them talk over a protocol. Totally doable, but not with the current Wayland protocol or (AFAIK) any proposed extension. (Although I guess the shell protocol has the start of something like this?)

eikenberry3• 1 year ago

I mean a higher level, window-manager specific protocol. Skipping all the lower level controls.

mackeye• 1 year ago

have a look at river, theyre currently working on something like this!

lugu• 1 year ago

https://github.com/riverwm/river#future-plans

smikhanov• 1 year ago

Looked at the source, it’s so compact, wow.

echelon• 1 year ago

It looks nothing like the Prolog I've seen before.

I'm quite amazed the author took a declarative language meant for logic and turned it on its head for managing windows as an actual application.

Bravo!

summarity• 1 year ago

Window management and constraints in general are a perfect fit for logic programming.

Y-bar• 1 year ago

Not just compact, but it also has lots of clearly written comments, love to see it!

raron2• 1 year ago

Does someone know a tutorial or something which explains how to get from "tutorial Prolog" to "real project Prolog", because that's not look anything like tutorial Prolog.

Prolog seems interesting, but any time I tried to do anything more than toy examples on my own, I got infinite recursion, unsolvable problems.

davidcox143• 1 year ago

This is one of the best resources for “real” Prolog:

https://www.metalevel.at/prolog

His YouTube videos are also incredibly good.

sidkshatriya• 1 year ago

I'll second that. Incredibly good quality videos. The precision of the narration is simply amazing. Even if you don't intend to practice Prolog in your programming life, it's worth a listen.

ioma8• 1 year ago

I have to concur. Markus Triska is best Prolog resource out there nowaday. Extremely well explained, using modern notations etc.

raron2• 1 year ago

Thanks.

bolangi• 1 year ago

Aside from the choice of language, I will be interested in what window managers are similar, or an inspiration for plwm.

jimmaswell2• 1 year ago

I installed all the libs and compiled this on Gentoo, but all I'm getting is a mouse cursor on a black screen.

johnisgood• 1 year ago

That is literally most tiling window managers. Check the keybindings. Start a terminal or something.

jimmaswell2• 1 year ago

I did read all the keybindings (as well as the entire README.md) hoping to find a "launch" or similar command but there was nothing relevant. "Increase number of master windows" was most promising but nothing happened. The only command that responded was super+shift+q to quit. Nothing abnormal going on in the Xorg or plwm logs.

ayrtondesozzla• 1 year ago

You've never used ratpoison, I see

5-• 1 year ago

this looks very impressive. forgive me a stupid question as a prolog outsider:

is this actually using any logical prolog features, or mostly just the 'functional' subset of prolog?

on a cursory look almost all annotated predicates are either 'det' or 'semidet', and none seem to have ? argument modes, so on the surface it looks like this is mostly straight functional code.

am i missing something important?

to be sure, prolog has much to recommend it even as a non-logic functional language: great syntax with probably the most flexible grammar out of all non-research languages (e.g. prolog's operator definition facility makes the ilk of haskell's seem like a toy), homoiconicity, etc.

but at least my expectation is perhaps for prolog code to make use more of the logical facilities.

mbrock• 1 year ago

I actually started hacking on a Prolog X11 WM last year, got distracted by other things but what I started with was a module to define BSP-style partitions using rational constraints, so you would be able e.g. to easily cycle between valid pane layouts.

major5052• 1 year ago

I don't know what amazes me more. The fact that someone used prolog to write a window manager, or the fact somone uses prolog at all.

DaiPlusPlus• 1 year ago

or the fact somone uses prolog at all.

I'll point your attention to 6 years ago: https://news.ycombinator.com/item?id=19279088

Another fun Prolog fact: Between 1996 and 2000, a Prolog program was distributed to tens of millions of users as part of Windows NT 4: https://web.archive.org/web/20040603192757/research.microsof... (via https://news.ycombinator.com/item?id=29528921 )

So do people use Prolog today? Given it's demonstrable that people use NT4 today, even if only for frivolous nostalgia trips or just an appreciation of _retro_-computing because if we can enjoy a mid-1990s abstract geometric screensaver today then it's no different to appreciating a 1960s Lava Lamp if you lived in the 1990s (presumably sat on the same desk and computer you're trying to install NT4 on).

major5052• 1 year ago

prett cool to know that. Guest is something you need to be in the middle to really know about. Like cobol.

Jerry2• 1 year ago

Are there any WMs that are implemented in JS and CSS? Or at least allow you to use JS/CSS? I’d love to be able to use web technologies to manage and decorate windows.

rabiescow• 1 year ago

Some of you hold on to X11 harder than Gollum and his ring...

Plwm – An X11 window manager written in Prolog

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