Chez Scheme is now free

[rohwer]

Dybvig's compiler course was exemplary. Say what you may about Scheme, you learned so much more in those classes. His Scheme Programming Language book is highly recommended. Especially check out his extended examples chapter: http://www.scheme.com/tspl4/examples.html#./examples:h0

[krat0sprakhar]

Thanks for this! I worked on implementing a type-inference algorithm last week and I wish I had stumbled upon the chapter on unification[1] earlier.

[0] - https://github.com/prakhar1989/type-inference

[1] - http://www.scheme.com/tspl4/examples.html#./examples:h10

[dman]

I thought scheme was like the beatles - people universally only had good things to say about it.

[smrq]

I was fortunate enough to take both his compiler course as well as a follow-up course involving optimization and hygienic macros. Brilliant man, fantastic teacher, and of course, he wrote a great compiler :)

[aalhour]

Thanks for referencing Dybvig's compiler course, can you point me to the course materials online, or share them with us here, if it's not an issue of copyrights of course?

I tried looking the course materials online but the Indiana University website gave me a 404 error page when I tried to access the course from Dybvig's website.

Thanks.

[michel-slm]

Paul is that you?

[FraaJad]

IIRC, this was a high performance scheme developed at Indiana University that was closed source for a long time.

Good on Cisco for open sourcing it.

I'm interested to hear what regular scheme programmers feel about this news.

[mathattack]

It's massively strange that this was closed source while at a public university, and open source under a public company.

[sesquipedalian]

I'm very excited about this. I've been using Chez as my performance benchmark target for my own Scheme implementation.

[groovy2shoes]

Scheme user here. I'm very excited about this, and I think I just changed my vacation plans for next week :D

[kkylin]

Can't say (yet). I've used a number of implementations: Gambit, MIT Scheme, PLT/Racket, and played around with Chicken. But never Chez, because it wasn't free.

[hga]

And aside from the JVM implementations and some works in progress the last time I checked, the only one with native instead of green threading.

[lispm]

Cisco prices from 2013

    SP-SW-LMIX0CH0 SP BASE Chez Scheme Dev Env for Wind,  Per Unit  $65.00
    SP-SW-LMIX0CHL SP BASE Chez Scheme Dev Env for Linux, Per 10    $325.00
    SP-SW-LMIX0CHW SP BASE Chez Scheme Dev Env for Wwind, Per 10    $325.00
    SP-SW-LMIX0CH1 SP BASE Chez Scheme Dev Env for Apple Mac,Per 10 $325.00
    SP-SW-LMIX0CHA SP BASE Chez Scheme Developm $65.00
    SP-SW-LMX01CHL SP BASE Chez Scheme Developm $65.00

[mayoff]

Chez Scheme price schedule I received in 2002:

    Chez Scheme Version 6
    Software License Fee Schedule
    V60901f
    
    Supported machine types:
       Intel 80x86 Linux 2.x
       Intel 80x86 Windows 95/98/ME/NT/2000
       Silicon Graphics IRIX 6.x
       Sun Sparc Solaris 2.x
    
    
    Classification                                  License fee (USD)
    -----------------------------------------------------------------
    Single Machines
      first machine per machine type                            $4000
      each additional machine                                    3000
    -----------------------------------------------------------------
    Site
      first machine type                                         9000
      two machine types                                         14000
      three or more machine types                               19000
    -----------------------------------------------------------------
    Academic Site (for qualified academic institutions)
      first machine type                                         4500
      two machine types                                          7000
      three or more machine types                                9500
    -----------------------------------------------------------------
    Corporate
      each machine type                                         24500

[longwaydown]

The $65-per-seat price was listed by a third-party Cisco vendor. There's never been any explanation as to how they came up with that price, nor whether anyone tried to purchase it that way. It was fun to tell people to get a license, especially given the normal prices (which someone else posted).

[sheepleherd]

For people interested in the legalities of licenses, it's released under the Apache License 2.0 which is a "free software" opensource license that is compatible when combined with GPL3, but not with GPL 1 or 2.

the Apache 2.0 license includes not just copyright but patent licensing, so the software will contain no hidden patent restrictions for patents owned by the creators and contributors.

[jordigh]

Why did you quote free software but not opensource? I am curious to know what the difference in your writing intended to convey.

[dmpk2k]

What is the library ecosystem like? This is ultimately what limits all other Scheme implementations.

[kkylin]

That is indeed a great question. Anyone know? I used to use Scheme for prototyping numerical code, etc., but have switched to Julia. Partly because Julia is more convenient in some ways, but mainly because of access to libraries, both native Julia libraries and Python libraries (via PyCall). I personally still prefer Scheme as a language, but missing libraries is a real problem.

[webkike]

Making fast scheme interpreters is something I always come back to, a timeless exercise that makes for a great way to decompress over a week (wow I'm a nerd). I'm excited to find some nuggets of micro-optimized gold!

[j-pb]

Compiler. Chez scheme is compiled with a nano-pass compiler. https://www.youtube.com/watch?v=Os7FE3J-U5Q

[xenophonf]

It's about time! Although I'm curious---how did Cisco end up owning it?

[longwaydown]

The short version: Dybvig left his faculty position at Indiana at the end of 2012 to join Cisco, and Cisco bought Cadence Research Systems (the company set up for licensing Chez Scheme), too. There's an FTC filing somewhere, but my Google-fu is failing me.

[brianobush]

If you look at scheme.com, you will see Copyright © 2011 Cadence Research Systems. Cisco bought Cadence back in 2012.

[rrnewton]

I used Chez Scheme for many years and loved its lightning fast compile times. For example, I'm not aware of any other full-scale compiler that can compile itself as fast as Chez can.

[PeCaN]

OberonSystem can build the whole compiler, OS, and applications in around 3 seconds.

[Johnny_Brahms]

Looking forward to having this integrated in geiser/emacs. I worked with chez recently, and it is really a high quality scheme implementation.

[dman]

Any details on what you were using it for? What did you like about it vs something like Racket?

[bitmadness]

Someone explain to me: Chez vs Gambit vs Chicken vs Bigloo. Which do I pick? Especially interested in parallel/multithreading abilities, standards compliance, and overall performance.

[tbirdz]

This page has a useful comparison between various scheme implementations. It's written by one of the authors of Guile Scheme: https://wingolog.org/archives/2013/01/07/an-opinionated-guid...

[jopython]

Out of the four you mentioned, only Chez has true posix threads.

[abc_lisper]

Why should I be interested in this - given there are many free high quality implementations for Scheme like Racket, Gambit etc?

[rntz]

Chez is known for being very fast, and for using state-of-the-art compiler technology.

[nickpsecurity]

This is great. I was hoping this would happen. The reason was a paper posted here in the past tracing its development from 8-bit days. I was impressed but knew it needed a community and OSS license.

Good.

[mark_l_watson]

Very cool!

I had trouble building it on Linux if I tried to set --installprefix= to a non-standard location, it built fine using the defaults. Nice!

On OS X, I have a clang version of gcc installed and perhaps because of that my build broke.

[mark_l_watson]

UPDATE: building on OS X:

I installed gcc-5 using brew, set "alias gcc=gcc-5", and then ./configure ; sudo make install worked fine.

[amttc]

Wow, I never thought they'd open source Chez. This is really cool.

[niccaluim]

Wow, this takes me back. I took intro CS at IU in 1993. At that time they were still teaching Scheme, using George Springer's Scheme and the Art of Programming and something like The Little Schemer (but not that because I guess it didn't come out for another two years). Delightful language with a really clean library. I always found Common Lisp's naming conventions to be—dare I say it?—PHP-esque in their irregularity. Scheme, meanwhile, actually has naming conventions. :)

[ams6110]

The Little LISPer (precursor to the Little Schemer) was definitely in print and used at IU in the 1980s. Maybe that was it?

[anta40]

A quote from BUILDING: "Building Chez Scheme under Windows is currently more complicated than it should be. It requires the configure script (and through it, the workarea script) to be run on a host system that supports a compatible shell, e.g., bash, and the various command-line tools employed by configure and workarea, e.g., sed and ln. For example, the host system could be a Linux or MacOS X machine. The release directory must be made available on a shared filesystem, e.g., samba, to a build machine running Windows. It is not presently possible to copy the release directory to a Windows filesystem due to the use of symbolic links."

Maybe someone have managed to build the Windows version?

[agumonkey]

Pretty great, always wanted to look at the implementation.

[defvar]

Wow, such a big news! I have heard so much praise about it and have been always want to use it. Now dream comes to true. Thanks!

[blaket]

anyone know how this became cisco's to release?

[detaro]

https://news.ycombinator.com/item?id=11572733

[dschiptsov]

This is good news. The code is worth reading. It is as good as MIT Scheme, and less esoteric than Gambit.)