Re: [racket-users] snake game

[Matthias Felleisen]

This is a working PB program: 

(require test-engine/racket-tests)
(require 2htdp/image)
(require 2htdp/universe)

(big-bang 100
  (to-draw (lambda (x) (circle (+ x 1) 'solid 'red)))
  (on-tick sub1)
  (stop-when zero?))

(test)


Now please do the rest of your homework yourself. 


> On Jan 26, 2019, at 2:55 PM, orenpa11  wrote:
> 
> Hi Matthias ,
> I am sorry but I still did get it.
> should I import the snake file that was written in "Beginning Student with 
> List Abbreviations"  and the code will be chnaged to  pretty big ?
> or only the "check-expect" is been chnaged from  "Beginning Student with List 
> Abbreviations"  to  pretty big ?
> Does Pretty Big has  drawing functions ?
> 
> Thanks,
> Or
> 
> On Friday, January 25, 2019 at 5:33:50 PM UTC+2, Matthias Felleisen wrote:
> 
> See below. I gave precise instructions. 
> 
> 
> > On Jan 25, 2019, at 10:27 AM, orenpa11 > 
> > wrote: 
> > 
> > OK, 
> > Got it , but how can I import the code of the snake program that was 
> > written in "Beginning Student with List Abbreviations"  and chnage it to  
> > pretty big ? 
> >   
> > 
> > On Friday, January 25, 2019 at 4:08:40 PM UTC+2, Robby Findler wrote: 
> > You've opened the right dialog. Now type "test-" into it. You should 
> > see the file appear. Click on it. 
> > 
> > Robby 
> > 
> > On Fri, Jan 25, 2019 at 7:53 AM orenpa11 > wrote: 
> > > 
> > > Hi, 
> > > Sorry but I did not get it. 
> > > should I add the path to the rkt file or add the code ? 
> > > 
> > > Thanks, 
> > > Or 
> > > 
> > > On Friday, January 25, 2019 at 1:39:12 PM UTC+2, Matthias Felleisen 
> > > wrote: 
> > >> 
> > >> 
> > >> DrRacket -> File -> Open Require Path -> enter test- -> use mouse 
> > >> 
> > >> 
> > >> On Jan 24, 2019, at 11:11 PM, orenpa11 > wrote: 
> > >> 
> > >> Hi 
> > >> where can I find the  test-engine ? 
> > >> I would like to copy the code  and  "play" with it. 
> > >> So I can understand it better . 
> > >> just copying the code is not helpful because I need to understand it. 
> > >> 
> > >> Thanks, 
> > >> Or 
> > >> 
> > >> On Thursday, January 24, 2019 at 11:54:34 PM UTC+2, Matthias Felleisen 
> > >> wrote: 
> > >>> 
> > >>> 
> > >>> Yes there is. Use (require test-engine/racket-tests) 
> > >>> at the top and (test) at the bottom. 
> > >>> 
> > >>> But it sounds like you’re copying and pasting homework 
> > >>> solutions. Hmph. 
> > >>> 
> > >>> 
> > >>> 
> > >>> 
> > >>> > On Jan 24, 2019, at 3:44 PM, orenpa11 > wrote: 
> > >>> > 
> > >>> > Hi Matthias , 
> > >>> > Unfortunately I need to write the project in pretty big language. 
> > >>> > The game is not written in pretty big language as far as I know. 
> > >>> > I thought that can copy andycode that was written in any language in 
> > >>> > racket to pretty big. 
> > >>> > Is there a way to transfer code that was written in  "Beginning 
> > >>> > Student with List Abbreviations" to pretty big ? 
> > >>> > 
> > >>> > Thanks, 
> > >>> > Or 
> > >>> > 
> > >>> > 
> > >>> > 
> > >>> > 
> > >>> > On Thursday, January 24, 2019 at 9:19:14 PM UTC+2, Matthias Felleisen 
> > >>> > wrote: 
> > >>> > 
> > >>> > 
> > >>> > Where did you find the snake game? 
> > >>> > Where did it say it’s written in Pretty Big? 
> > >>> > 
> > >>> > We have not used Pretty Big in over a decade in education, 
> > >>> > neither does anyone in the Racket edu community proper. 
> > >>> > 
> > >>> > This community supports people readily wth answers, but 
> > >>> > we need to know what you know. 
> > >>> > 
> > >>> > — Matthias 
> > >>> > 
> > >>> > 
> > >>> > 
> > >>> > 
> > >>> > > On Jan 24, 2019, at 12:56 PM, orenpa11 > wrote: 
> > >>> > > 
> > >>> > > Hi 
> > >>> > > I need to create a project in pertty big . 
> > >>> > > why this code is not been supported ? 
> > >>> > > 
> > >>> > > Thanks, 
> > >>> > > Or 
> > >>> > > 
> > >>> > > On Thursday, January 24, 2019 at 3:29:11 PM UTC+2, Kieron Hardy 
> > >>> > > wrote: 
> > >>> > > The language you should be using is "Beginning Student with List 
> > >>> > > Abbreviations". 
> > >>> > > 
> > >>> > > On Jan 24, 2019, at 4:33 AM, orenpa11 > wrote: 
> > >>> > > 
> > >>> > >> Hi, 
> > >>> > >> when I removed the line 
> > >>> > >> #reader(lib "htdp-beginner-abbr-reader.ss" "lang")((modname 
> > >>> > >> snake-full) (read-case-sensitive #t) (teachpacks ()) 
> > >>> > >> (htdp-settings #(#t constructor repeating-decimal #f #t none #f 
> > >>> > >> ( 
> > >>> > >> 
> > >>> > >> And changed the  language to pretty big. 
> > >>> > >> I recived this error: 
> > >>> > >> Welcome to DrRacket, version 7.1 [3m]. 
> > >>> > >> Language: Pretty Big; memory limit: 128 MB. 
> > >>> > >> . . check-expect: undefined; 
> > >>> > >>  cannot reference an identifier before its definition 
> > >>> > >> 
> > >>> > >> Any idea ? 
> > >>> > >> 
> > >>> > >> Thanks, 
> > >>> > >> Or 
> > >>> > >> 
> > >>> > >> 
> > >>> > >> 
> > >>> > >> 
> > >>> > >> 
> > >>> > >> On Wednesday, January 23, 2019 at 10:49:01 PM UTC+2, Kieron Hardy 
> > >>> > >> wrote: 
> > 

Re: [racket-users] snake game

[orenpa11]

Hi Matthias ,
I am sorry but I still did get it.
should I import the snake file that was written in "Beginning Student with 
List Abbreviations"  and the code will be chnaged to  pretty big ?
or only the "check-expect" is been chnaged from  "Beginning Student with 
List Abbreviations"  to  pretty big ?
Does Pretty Big has  drawing functions ?

Thanks,
Or

On Friday, January 25, 2019 at 5:33:50 PM UTC+2, Matthias Felleisen wrote:
>
>
> See below. I gave precise instructions. 
>
>
> > On Jan 25, 2019, at 10:27 AM, orenpa11 > 
> wrote: 
> > 
> > OK, 
> > Got it , but how can I import the code of the snake program that was 
> written in "Beginning Student with List Abbreviations"  and chnage it to 
>  pretty big ? 
> >   
> > 
> > On Friday, January 25, 2019 at 4:08:40 PM UTC+2, Robby Findler wrote: 
> > You've opened the right dialog. Now type "test-" into it. You should 
> > see the file appear. Click on it. 
> > 
> > Robby 
> > 
> > On Fri, Jan 25, 2019 at 7:53 AM orenpa11  wrote: 
> > > 
> > > Hi, 
> > > Sorry but I did not get it. 
> > > should I add the path to the rkt file or add the code ? 
> > > 
> > > Thanks, 
> > > Or 
> > > 
> > > On Friday, January 25, 2019 at 1:39:12 PM UTC+2, Matthias Felleisen 
> wrote: 
> > >> 
> > >> 
> > >> DrRacket -> File -> Open Require Path -> enter test- -> use mouse 
> > >> 
> > >> 
> > >> On Jan 24, 2019, at 11:11 PM, orenpa11  wrote: 
> > >> 
> > >> Hi 
> > >> where can I find the  test-engine ? 
> > >> I would like to copy the code  and  "play" with it. 
> > >> So I can understand it better . 
> > >> just copying the code is not helpful because I need to understand it. 
> > >> 
> > >> Thanks, 
> > >> Or 
> > >> 
> > >> On Thursday, January 24, 2019 at 11:54:34 PM UTC+2, Matthias 
> Felleisen wrote: 
> > >>> 
> > >>> 
> > >>> Yes there is. Use (require test-engine/racket-tests) 
> > >>> at the top and (test) at the bottom. 
> > >>> 
> > >>> But it sounds like you’re copying and pasting homework 
> > >>> solutions. Hmph. 
> > >>> 
> > >>> 
> > >>> 
> > >>> 
> > >>> > On Jan 24, 2019, at 3:44 PM, orenpa11  wrote: 
> > >>> > 
> > >>> > Hi Matthias , 
> > >>> > Unfortunately I need to write the project in pretty big language. 
> > >>> > The game is not written in pretty big language as far as I know. 
> > >>> > I thought that can copy andycode that was written in any language 
> in racket to pretty big. 
> > >>> > Is there a way to transfer code that was written in  "Beginning 
> Student with List Abbreviations" to pretty big ? 
> > >>> > 
> > >>> > Thanks, 
> > >>> > Or 
> > >>> > 
> > >>> > 
> > >>> > 
> > >>> > 
> > >>> > On Thursday, January 24, 2019 at 9:19:14 PM UTC+2, Matthias 
> Felleisen wrote: 
> > >>> > 
> > >>> > 
> > >>> > Where did you find the snake game? 
> > >>> > Where did it say it’s written in Pretty Big? 
> > >>> > 
> > >>> > We have not used Pretty Big in over a decade in education, 
> > >>> > neither does anyone in the Racket edu community proper. 
> > >>> > 
> > >>> > This community supports people readily wth answers, but 
> > >>> > we need to know what you know. 
> > >>> > 
> > >>> > — Matthias 
> > >>> > 
> > >>> > 
> > >>> > 
> > >>> > 
> > >>> > > On Jan 24, 2019, at 12:56 PM, orenpa11  
> wrote: 
> > >>> > > 
> > >>> > > Hi 
> > >>> > > I need to create a project in pertty big . 
> > >>> > > why this code is not been supported ? 
> > >>> > > 
> > >>> > > Thanks, 
> > >>> > > Or 
> > >>> > > 
> > >>> > > On Thursday, January 24, 2019 at 3:29:11 PM UTC+2, Kieron Hardy 
> wrote: 
> > >>> > > The language you should be using is "Beginning Student with List 
> Abbreviations". 
> > >>> > > 
> > >>> > > On Jan 24, 2019, at 4:33 AM, orenpa11  wrote: 
> > >>> > > 
> > >>> > >> Hi, 
> > >>> > >> when I removed the line 
> > >>> > >> #reader(lib "htdp-beginner-abbr-reader.ss" "lang")((modname 
> snake-full) (read-case-sensitive #t) (teachpacks ()) (htdp-settings #(#t 
> constructor repeating-decimal #f #t none #f ( 
> > >>> > >> 
> > >>> > >> And changed the  language to pretty big. 
> > >>> > >> I recived this error: 
> > >>> > >> Welcome to DrRacket, version 7.1 [3m]. 
> > >>> > >> Language: Pretty Big; memory limit: 128 MB. 
> > >>> > >> . . check-expect: undefined; 
> > >>> > >>  cannot reference an identifier before its definition 
> > >>> > >> 
> > >>> > >> Any idea ? 
> > >>> > >> 
> > >>> > >> Thanks, 
> > >>> > >> Or 
> > >>> > >> 
> > >>> > >> 
> > >>> > >> 
> > >>> > >> 
> > >>> > >> 
> > >>> > >> On Wednesday, January 23, 2019 at 10:49:01 PM UTC+2, Kieron 
> Hardy wrote: 
> > >>> > >> It seems the metadata lines added by DrRacket (mentioned by 
> John) are processed when the a source file is loaded into DrRacket (via the 
> menu option File/Open), but are not processed if the source code is 
> directly copied (e.g. from a browser window) into a DrRacket window and 
> then executed with the 'Run' button. 
> > >>> > >> 
> > >>> > >> The metadata includes a #reader directive, e.g.: 
> > >>> > >> (#reader(lib "htdp-beginner-abbr-reader.ss" 

Re: [racket-users] Beginning of the end for googlegroups?

[Tomasz Rola]

On Fri, Jan 25, 2019 at 05:48:32PM -0700, Jack Rosenthal wrote:
> On Fri, 25 Jan 2019 at 23:59 +0100, 'Paulo Matos' via Racket Users wrote:
> > Not sure of the size of the mailing list but I wonder if this is the
> > beginning of the end and we should have instead a plan B.
> 
> We could always go back to Mailman...
> 
> Or, if someone started working on a Racket-based alternative to Mailman,
> I'm certain people around here would be very excited to use it.

For archival reason, I claim that some people would not be excited by
such choice. Mailman, for better or worse, has bigger user base, thus
should have such minutia as security problems resolved faster and
maybe in better ways.

Of course if someone writes a replacement and it is indeed better than
original, that would be another thing. Perhaps the effort should start
with explaining what should be improved. (Note: I am not involved in
any way, I am just saying - overally, I am excited about improving
software - for example, can it be claimed that Racket-based clone of
Mailman would be more secure? would deal better with spammorz,
i.e. treat them worse than original? etc).

-- 
Regards,
Tomasz Rola

--
** A C programmer asked whether computer had Buddha's nature.  **
** As the answer, master did "rm -rif" on the programmer's home**
** directory. And then the C programmer became enlightened...  **
** **
** Tomasz Rola  mailto:tomasz_r...@bigfoot.com **

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Re: [racket-users] Beginning of the end for googlegroups?

[Neil Van Dyke]

FWIW, I still agree with the original decision to move the lists to 
Google Groups, given the circumstances.  Also, IIRC, John asked the 
community for comments before doing it.  I understood the choice then, 
and, more recently, I chose Google Groups for the `racket-money` list, 
after similar mixed feelings.


(In the field lately, for various reasons, there's sometimes a 
phenomenon of casually making IT infrastructure dependencies on a dozen 
different questionable third-parties and their bloats, without much 
apparent thought.  So I understand wondering whether a particular choice 
fell under this phenomenon.  In the case of Racket email lists, however, 
it was a knowledgeable and thoughtful decision.  And, AFAIK, Google 
Groups is still a reasonable pragmatic choice for free public email 
lists in general.)


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Re: [racket-users] Collections and data structures wishlist?

[Jesse Alama]

On 26 Jan 2019, at 15:39, Hendrik Boom wrote:


On Sat, Jan 26, 2019 at 09:19:11AM -0500, Matthias Felleisen wrote:


On Jan 26, 2019, at 9:03 AM, Sorawee Porncharoenwase 
 wrote:


Matthias, where can I find this "History of Clojure"? I searched for
"It is better to have 100 transducers ..."


I'd love even to know what he *meant* by that.  I always thought 10x10
made for more modularity.


I'm pretty sure he was just riffing on the same Perlis theme we know, 
repackaged for a Clojure audience 
(https://clojure.org/reference/transducers). IIRC the Clojure community 
went through a phase a few years ago where transducers were all the 
rage.


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Re: [racket-users] Beginning of the end for googlegroups?

[Hendrik Boom]

On Sat, Jan 26, 2019 at 09:15:05AM -0500, Hendrik Boom wrote:
> 
> Google dowa have Google takeout.  I've used it to download my 
> contributions to Google plus.  No, it didn't quite do everything; in 
> particular I've notices that images are missong from reposted posts.

> 
> But I believe one of the options was to download a group.  I suspect only 
> the group administrator can do that.  It is probably worth trying it just 
> in case it's an easy way to ensure we can have our own mailing list 
> archive.

It looks as if Google Takeout will only find the user's contributions to 
the group.  But it may be different for a group administrators.

A pity.  There are a few groups I'd like to download a complete history 
of.

-- hendrik

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Re: [racket-users] Collections and data structures wishlist?

[Hendrik Boom]

On Sat, Jan 26, 2019 at 09:19:11AM -0500, Matthias Felleisen wrote:
> 
> > On Jan 26, 2019, at 9:03 AM, Sorawee Porncharoenwase 
> >  wrote:
> > 
> > Matthias, where can I find this "History of Clojure"? I searched for 
> > "It is better to have 100 transducers ..."

I'd love even to know what he *meant* by that.  I always thought 10x10 
made for more modularity.

> > and found no result (besides this very thread). I also searched for 
> > "History of Clojure" and only found this tweet 
> >  from Rich 
> > Hickey in Nov 2018, and it seems he was still writing it back then. 
> > Is it available for public to view now?
> > 
> 
> 
> Unpublished notes. But I believe he said something like that during 
> his StrangeLoop presentation of transducers in Clojure. 
> 
> 
> > If we take an argument that we can encode a tuple with a list and 
> > get all benefits from list operations, why don't we (define-values 
> > (bool/c true false) (values int/c 1 0))? Why don't we (Church) encode 
> > everything to lambdas?
> 
> 
> Functions are infinite data, lists are finite.

The theoretical difference between the two lies in the Turing 
undecidability theorems.
Functions in Racket are, however, finitely represented.

The practical difference lies in efficiency.

> You need to develop good taste for good compromises. 
> 
> I am the one who pushed PLT Scheme/Racket into the static corner 
> (e.g., structs). But the place in the middle is where the sweet spot 
> is. 

The Buddha's middle way.

Everything in moderation, even moderation in moderation.

-- hendrik

> 
> — Matthias, radical centrist with nuanced opinions often stated in 
> provocative ways :) 
> 

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Re: [racket-users] Beginning of the end for googlegroups?

[Matthew Flatt]

At Sat, 26 Jan 2019 09:15:05 -0500, Hendrik Boom wrote:
> Annoying, considering that we used to have our own mailing list long ago.
> Why did we ever switch?

Because no one stepped up to maintain the maintain the mailing list.

Running a mail server is a huge pain, and those of us who were doing it
got tired of spending our time that way. We asked for volunteers. There
were no takers. As other have suggested, we went with Google groups
because it requires the last effort of any mechanism we could find.

Even maintaining the Google group is not effortless, but John Clements
has kindly taken care of it for years.

Thank you, John!

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Re: [racket-users] Collections and data structures wishlist?

[Matthias Felleisen]

> On Jan 26, 2019, at 9:03 AM, Sorawee Porncharoenwase 
>  wrote:
> 
> Matthias, where can I find this "History of Clojure"? I searched for "It is 
> better to have 100 transducers ..." and found no result (besides this very 
> thread). I also searched for "History of Clojure" and only found this tweet 
>  from Rich Hickey 
> in Nov 2018, and it seems he was still writing it back then. Is it available 
> for public to view now?
> 


Unpublished notes. But I believe he said something like that during his 
StrangeLoop presentation of transducers in Clojure. 


> If we take an argument that we can encode a tuple with a list and get all 
> benefits from list operations, why don't we (define-values (bool/c true 
> false) (values int/c 1 0))? Why don't we (Church) encode everything to 
> lambdas?


Functions are infinite data, lists are finite. You need to develop good taste 
for good compromises. 

I am the one who pushed PLT Scheme/Racket into the static corner (e.g., 
structs). But the place in the middle is where the sweet spot is. 

— Matthias, radical centrist with nuanced opinions often stated in provocative 
ways :) 

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Re: [racket-users] Beginning of the end for googlegroups?

[Hendrik Boom]

On Fri, Jan 25, 2019 at 08:51:18PM -0500, Neil Van Dyke wrote:
> Google has shut down many services, including some surprising ones. Without
> getting alarmed, I think it's reassuring that we could handle an end-of-life
> of Google Groups on fairly short notice, if that ever happened...
> 
> Regarding hosting of the email list server... worst case, were Google Groups
> to shut down with no good migration offering... if we can't find a turn-key
> email list service we like, we could always run the time-honored MailMan on
> either one of the affiliated universities' in-house systems (if the
> non-owned .org domain name isn't a problem for that .edu), or on
> Linode/AWS/etc.

Google dowa have Google takeout.  I've used it to download my 
contributions to Google plus.  No, it didn't quite do everything; in 
particular I've notices that images are missong from reposted posts.

But I believe one of the options was to download a group.  I suspect only 
the group administrator can do that.  It is probably worth trying it just 
in case it's an easy way to ensure we can have our own mailing list 
archive.

> 
> That part doesn't have to be much work (click a few buttons with a turn-key
> hoster, copy the user list, point a DNS MX record at the new server),
> *unless* we have to set up a new MailMan install (which implies a lot more
> sys-admin tasks, immediate and then ongoing maintenance).

Annoying, considering that we used to have our own mailing list long ago.
Why did we ever switch?

> 
> The tricky parts of moving are not with the email list server itself, but
> preserving the archive and citation links:
> 
> * Were Google Groups shut down in such a way that citation links (for
> messages and threads) were broken (no read-only version, no configurable
> redirects), we'd partly have to accept that there will be broken links. 
> Were we to scrape the archive, we might be able to preserve the info about
> the old links, and then put up a Web page that makes it easier for people to
> reconstruct a link on demand, but that's significant work for perhaps little
> benefit.

How hard is it to automatically detect a link to the google group site in 
a message?

-- hendrik

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Re: [racket-users] Collections and data structures wishlist?

[Sorawee Porncharoenwase]

Matthias, where can I find this "History of Clojure"? I searched for "It is 
better to have 100 transducers ..." and found no result (besides this very 
thread). I also searched for "History of Clojure" and only found this tweet 
 from Rich 
Hickey in Nov 2018, and it seems he was still writing it back then. Is it 
available for public to view now?

If we take an argument that we can encode a tuple with a list and get all 
benefits from list operations, why don't we (define-values (bool/c true 
false) (values int/c 1 0))? Why don't we (Church) encode everything to 
lambdas?

On Friday, January 25, 2019 at 4:51:10 PM UTC-8, Matthias Felleisen wrote:
>
>
> Yes. See Clojure history. — Matthias
>
>
>
> On Jan 25, 2019, at 4:21 PM, Jack Firth > 
> wrote:
>
> I don't intend to make these operations impossible or even difficult. One 
> of the other things on my wishlist is a transducers library, which would 
> IMO be a good fit for a lot of the logic that Racket currently provides as 
> list-processing functions. So if you want to process tuples as generalized 
> streams of values, you'd use transducers on them. But if you want to 
> process tuples as *tuples*, you'd use tuple-processing functions. I think 
> mapping and filtering fit the first category more than the second. This 
> kind of divide makes it much easier to support a wide array of data 
> structures without copying the entire list processing API for each one.
>
> On Fri, Jan 25, 2019 at 12:51 PM Matthias Felleisen  > wrote:
>
>>
>> > On Jan 25, 2019, at 3:46 PM, Thomas F. Burdick > > wrote:
>> > 
>> > 
>> > 
>> > On January 25, 2019 8:33:09 PM GMT+01:00, Jack Firth <
>> jackh...@gmail.com > wrote:
>> >> 
>> >> Due to the kind of data that would go in tuples - namely, a fixed-sized
>> >> heterogeneous collection of values - a function probably *shouldn't*
>> >> use
>> >> map and filter to process tuples. A program that calls filter on an
>> >> x-y-z
>> >> coordinate tuple is likely incorrect and not what the programmer
>> >> intended.
>> > 
>> > Funny you should pick that as an example. I work in a CAD environment 
>> where points are two-item lists, and polygon outlines are lists of points. 
>> You'd be surprised how often it's useful to use ordinary list functions on 
>> points.
>>
>>
>> That’s precisely the kind of programming I had in mind. Racket is one of 
>> the few languages where you can eat your cake and have it anyways. Why take 
>> away that strength? 
>
>
>

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Re: [racket-users] Collections and data structures wishlist?

[Matthias Felleisen]

> On Jan 26, 2019, at 8:31 AM, Hendrik Boom  wrote:
> 
> On Fri, Jan 25, 2019 at 07:50:56PM -0500, Matthias Felleisen wrote:
>> 
>> Yes. See Clojure history. — Matthias
> 
> Given the amount of text you have quoted, it's not clear what you are 
> saying yes to.


Hickey: "we tweak Perlis one final time - "It is best to have 100 functions 
operate on NO data structure”.” 

[[ He means to have 100 transducers on Interfaces, instead of 10 x 10 functions 
on concrete data structures. ]]

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Re: [racket-users] Collections and data structures wishlist?

[Hendrik Boom]

On Fri, Jan 25, 2019 at 11:33:09AM -0800, Jack Firth wrote:
> 
> Due to the kind of data that would go in tuples - namely, a fixed-sized
> heterogeneous collection of values - a function probably *shouldn't* use
> map and filter to process tuples. A program that calls filter on an x-y-z
> coordinate tuple is likely incorrect and not what the programmer intended.

There are often times I want to process the elements of coordinate tuples 
uniformly, and oftern times I want to treat them separately.  This seems 
like a case where I'd want both tupe operations and list operations on 
the same data.

-- hendrik

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[racket-users] Re: Beginning of the end for googlegroups?

[Zelphir Kaltstahl]

I've always wondered, why Racket uses Google groups and guesses, that it
is because of low setup effort required. In such cases the darker side
of lock in system shows: Not so easy to get away from them. When the
lights go out it is possible to lose everything. It's very similar to
the effect some wiki systems have (for example confluence wiki), where
you have no good "export everything on this page" option. The most
natural export formats not available etc. Personally I'd be all for
something independent from Google or big companies.

Of course it might be a lot of work without proper export ways.

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