[racket-users] `raco pkg install` from private GitHub repo?

[Matthew Butterick]

Seems like this has been asked before. But the exact search query is eluding 
me. 

One can do `raco pkg install http://url/to/public/git/repo`.

Is it possible to use a private repo as the target of `raco pkg install`? 
(IIRC, no.)

What is the least painful workaround? Make a local clone of the private repo 
with git, and then do `raco pkg install /path/to/local/clone/of/private/repo`? 
(And then subsequent updates can be `git pull` + `raco setup`)

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Re: [racket-users] build-path/convention-type failure

[Matthew Flatt]

At Mon, 23 Oct 2017 18:56:27 -0400, David Storrs wrote:
> The signature for build-path/convention-type is:
> [...]
> What gives?

The blue-box contract on `build-path/convention-type` in the
documentation does not encode all of the constraints of the function
(in much the same way that the blue-box contract on `vector-ref` doesn't
encode the constraint that the second argument is in bounds).

For both `build-path` and `build-path/convention-type`, strings are
always treated as paths for the current system --- and they're
converted to path values based on the current system's locale --- so
they cannot be mixed with paths using a different convention.

You can use byte strings and `bytes->path` to construct a path for any
convention. Unlike strings, byte strings can reliably encode paths.


> Also, while we're at it, what do REL and RED stand for in the docs?
> https://docs.racket-lang.org/reference/windowspaths.html

They're short for "relative" and "relative to a drive", respectively.

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Re: [racket-users] Science graphics with Racket?

[Lawrence Bottorff]

This is amazing! Thank you very much!

On Mon, Oct 23, 2017 at 4:49 PM, Jens Axel Søgaard 
wrote:

> I forgot to show how to make a graph.
>
> #lang racket
> (require racket/draw metapict metapict/graph)
>
> (set-curve-pict-size 300 300)  ; width and height of image
> (ahlength  1.0); size of arrow head
>
> (define (f x) (sin x))
>
> (define p
>   (with-window (window -12 12 -12 12) ; xmin, xmax, ymin, ymax
> (draw (draw-arrow (curve (pt -10   0) -- (pt 10  0)))  ; x-axis
>   (draw-arrow (curve (pt   0 -10) -- (pt  0 10)))  ; y-axis
>   (label-rt  "x" (pt 10.2 0))  ; label for x
> axis
>   (label-top "y" (pt 0 10.2))  ; label for y
> axis
>   (color "blue" (draw (circle (pt 2 1) 3))); center (2,1)
> radius 3
>   (color "red"  (draw (graph f -10 10 #:samples 50))
>
> p ; show pict in repl
>
> (define (save-pict-as-svg p width height filename [exists 'replace])
>   (define dc (new svg-dc%
>   [width width]
>   [height height]
>   [output filename]
>   [exists exists]))
>   (send dc start-doc "An SVG Test")  ; a message
>   (send dc start-page)
>   (draw-pict p dc 0 0)
>   (send dc end-page)
>   (send dc end-doc))
>
>
>
> (save-pict-as-svg p 300 300 "output.svg")
>
>
> 2017-10-23 21:39 GMT+02:00 Jens Axel Søgaard :
>
>> Here is how to do it using MetaPict:
>>
>> #lang racket
>> (require racket/draw metapict)
>>
>> (set-curve-pict-size 300 300)  ; width and height of image
>> (ahlength  1.0); size of arrow head
>>
>> (define p
>>   (with-window (window -12 12 -12 12) ; xmin, xmax, ymin, ymax
>> (draw (draw-arrow (curve (pt -10   0) -- (pt 10  0)))  ; x-axis
>>   (draw-arrow (curve (pt   0 -10) -- (pt  0 10)))  ; y-axis
>>   (label-rt  "x" (pt 10.2 0))  ; label for x
>> axis
>>   (label-top "y" (pt 0 10.2))  ; label for y
>> axis
>>   (circle (pt 2 1) 3   ; center (2,1)
>> radius 3
>>
>> p ; show pict in repl
>>
>> (define (save-pict-as-svg p width height filename [exists 'replace])
>>   (define dc (new svg-dc%
>>   [width width]
>>   [height height]
>>   [output filename]
>>   [exists exists]))
>>   (send dc start-doc "An SVG Test")  ; a message
>>   (send dc start-page)
>>   (draw-pict p dc 0 0)
>>   (send dc end-page)
>>   (send dc end-doc))
>>
>>
>>
>> (save-pict-as-svg p 300 300 "output.svg")
>>
>>
>> 2017-10-23 21:04 GMT+02:00 Lawrence Bottorff :
>>
>>> I'd like to use Racket to generate scalable (svg?) graphics like gnuplot
>>> or GeoGebra does. For example, I'd like to create a cartesian coordinate
>>> graph system, then draw functions on it. One thing in particular would be
>>> to draw a graph of a circle based on the standard form of a circle, e.g.,
>>> x^2 + y^2 = r^2. Again, I'd prefer being able to create an svg file. Is
>>> there a tutorial that might give me more insight than the reference pages
>>> or the Quick: An Introduction to Racket with Pictures? Or am I barking up
>>> the wrong tree?
>>>
>>> LB
>>>
>>> --
>>> You received this message because you are subscribed to the Google
>>> Groups "Racket Users" group.
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>>> an email to racket-users+unsubscr...@googlegroups.com.
>>> For more options, visit https://groups.google.com/d/optout.
>>>
>>
>>
>>
>> --
>> --
>> Jens Axel Søgaard
>>
>>
>
>
> --
> --
> Jens Axel Søgaard
>
>

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Re: [racket-users] Open source projects

[Guthrie Price]

Thank you all so much for your comments (the resulting discussion was also
entertaining and unexpected).

If I were to implement path auto-completion, would it be useful if it
wasn’t integrated into DrRacket? I am not precisely sure what I would be
adding this functionality to if not DrRacket.

On Sunday, October 22, 2017, Neil Van Dyke  wrote:

> I could be missing something, but I think a filename completion procedure
> (not the DrRacket integration part) might be a doable exercise for a
> budding Racket programmer, so long as they already have a basic familiarity
> with using the filesystem and shell as a normal user.
>
> Point them to the "Paths" and "Filesystem" sections of the Racket
> Reference, and tell them they just need a few procedures from each
> (probably including `split-path` and `directory-list`).
>
> They might want to first make a procedure like this:
>
> (path-completions path-or-string?)
> ==> (listof completion-string)
>
> And then make a second procedure, which uses the first procedure, then
> adds an additional step, to let it return two values instead of one:
>
> (path-completion-prefix-and-suffixes path-or-string?)
> ==> (values prefix-string-shared-by-all-completions
> (listof completion-remainder-after-any-shared-prefix-string))
>
> Then, when a user is interactively doing completion (like when they hit
> the Tab key in a shell), the first value returned by that second procedure
> is what would get added automatically to the path.  The second value is the
> list of possible completions following that shared prefix.
>
> There are a few special cases to consider, but most should be easy to
> recognize and work through, just by thinking methodically about each point
> in your code.  For example, what do you do when the input path is relative,
> or when when there are no completions, or when the path is invalid or
> nonexistent or permissions-inaccessible, or when your path is already
> complete.  One case that's not obvious from the code: if the path is
> already complete and is a directory, a shell usually completes a directory
> separator, so consider whether you want to do that.
>
> To make unit tests for these, they'll have to also look at more of the
> "Filesystem" section of the Racket Reference, to create and remove files
> and directories.
>
> (I think wrapping a shell process, robustly, is much more difficult.)
>
> --
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[racket-users] build-path/convention-type failure

[David Storrs]

The signature for build-path/convention-type is:

(build-path/convention-type type
  base
  sub ...) → path-for-some-system?

type : (or/c 'unix 'windows)
base : (or/c path-string? path-for-some-system? 'up 'same)
sub : (or/c (and/c (or/c path-string? path-for-some-system?)
(not/c complete-path?))
 (or/c 'up 'same))

I'm running on OSX 10.11.6 (El Capitan) and I don't understand the
results I'm getting:

-> (define p "C:\\foo\\bar")

-> (build-path p)
#  ; NB:  This is *not* a windows path, despite
looking like one

-> (build-path/convention-type 'windows 'up 'up)
#  ; NB: this is a Windows path

-> (build-path/convention-type 'windows p)
; build-path/convention-type: specified convention incompatible with string
;   path element
;   path element: "C:\\foo\\bar"
;   convention: 'windows
; [,bt for context]

-> (build-path/convention-type 'windows "/foo/bar")
(build-path/convention-type 'windows "/foo/bar")
; build-path/convention-type: specified convention incompatible with string
;   path element
;   path element: "/foo/bar"
;   convention: 'windows
; [,bt for context]

What gives?

Also, while we're at it, what do REL and RED stand for in the docs?
https://docs.racket-lang.org/reference/windowspaths.html

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Re: [racket-users] Science graphics with Racket?

[Jens Axel Søgaard]

I forgot to show how to make a graph.

#lang racket
(require racket/draw metapict metapict/graph)

(set-curve-pict-size 300 300)  ; width and height of image
(ahlength  1.0); size of arrow head

(define (f x) (sin x))

(define p
  (with-window (window -12 12 -12 12) ; xmin, xmax, ymin, ymax
(draw (draw-arrow (curve (pt -10   0) -- (pt 10  0)))  ; x-axis
  (draw-arrow (curve (pt   0 -10) -- (pt  0 10)))  ; y-axis
  (label-rt  "x" (pt 10.2 0))  ; label for x
axis
  (label-top "y" (pt 0 10.2))  ; label for y
axis
  (color "blue" (draw (circle (pt 2 1) 3))); center (2,1)
radius 3
  (color "red"  (draw (graph f -10 10 #:samples 50))

p ; show pict in repl

(define (save-pict-as-svg p width height filename [exists 'replace])
  (define dc (new svg-dc%
  [width width]
  [height height]
  [output filename]
  [exists exists]))
  (send dc start-doc "An SVG Test")  ; a message
  (send dc start-page)
  (draw-pict p dc 0 0)
  (send dc end-page)
  (send dc end-doc))



(save-pict-as-svg p 300 300 "output.svg")


2017-10-23 21:39 GMT+02:00 Jens Axel Søgaard :

> Here is how to do it using MetaPict:
>
> #lang racket
> (require racket/draw metapict)
>
> (set-curve-pict-size 300 300)  ; width and height of image
> (ahlength  1.0); size of arrow head
>
> (define p
>   (with-window (window -12 12 -12 12) ; xmin, xmax, ymin, ymax
> (draw (draw-arrow (curve (pt -10   0) -- (pt 10  0)))  ; x-axis
>   (draw-arrow (curve (pt   0 -10) -- (pt  0 10)))  ; y-axis
>   (label-rt  "x" (pt 10.2 0))  ; label for x
> axis
>   (label-top "y" (pt 0 10.2))  ; label for y
> axis
>   (circle (pt 2 1) 3   ; center (2,1)
> radius 3
>
> p ; show pict in repl
>
> (define (save-pict-as-svg p width height filename [exists 'replace])
>   (define dc (new svg-dc%
>   [width width]
>   [height height]
>   [output filename]
>   [exists exists]))
>   (send dc start-doc "An SVG Test")  ; a message
>   (send dc start-page)
>   (draw-pict p dc 0 0)
>   (send dc end-page)
>   (send dc end-doc))
>
>
>
> (save-pict-as-svg p 300 300 "output.svg")
>
>
> 2017-10-23 21:04 GMT+02:00 Lawrence Bottorff :
>
>> I'd like to use Racket to generate scalable (svg?) graphics like gnuplot
>> or GeoGebra does. For example, I'd like to create a cartesian coordinate
>> graph system, then draw functions on it. One thing in particular would be
>> to draw a graph of a circle based on the standard form of a circle, e.g.,
>> x^2 + y^2 = r^2. Again, I'd prefer being able to create an svg file. Is
>> there a tutorial that might give me more insight than the reference pages
>> or the Quick: An Introduction to Racket with Pictures? Or am I barking up
>> the wrong tree?
>>
>> LB
>>
>> --
>> You received this message because you are subscribed to the Google Groups
>> "Racket Users" group.
>> To unsubscribe from this group and stop receiving emails from it, send an
>> email to racket-users+unsubscr...@googlegroups.com.
>> For more options, visit https://groups.google.com/d/optout.
>>
>
>
>
> --
> --
> Jens Axel Søgaard
>
>


-- 
-- 
Jens Axel Søgaard

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Re: [racket-users] Science graphics with Racket?

[Jon Zeppieri]

On Mon, Oct 23, 2017 at 3:04 PM, Lawrence Bottorff  wrote:
> I'd like to use Racket to generate scalable (svg?) graphics like gnuplot or
> GeoGebra does. For example, I'd like to create a cartesian coordinate graph
> system, then draw functions on it. One thing in particular would be to draw
> a graph of a circle based on the standard form of a circle, e.g., x^2 + y^2
> = r^2. Again, I'd prefer being able to create an svg file. Is there a
> tutorial that might give me more insight than the reference pages or the
> Quick: An Introduction to Racket with Pictures? Or am I barking up the wrong
> tree?
>
> LB
>

Hi Lawrence,

Have you looked at the plot library? [https://docs.racket-lang.org/plot/]

- Jon

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Re: [racket-users] Science graphics with Racket?

[Jens Axel Søgaard]

Here is how to do it using MetaPict:

#lang racket
(require racket/draw metapict)

(set-curve-pict-size 300 300)  ; width and height of image
(ahlength  1.0); size of arrow head

(define p
  (with-window (window -12 12 -12 12) ; xmin, xmax, ymin, ymax
(draw (draw-arrow (curve (pt -10   0) -- (pt 10  0)))  ; x-axis
  (draw-arrow (curve (pt   0 -10) -- (pt  0 10)))  ; y-axis
  (label-rt  "x" (pt 10.2 0))  ; label for x
axis
  (label-top "y" (pt 0 10.2))  ; label for y
axis
  (circle (pt 2 1) 3   ; center (2,1)
radius 3

p ; show pict in repl

(define (save-pict-as-svg p width height filename [exists 'replace])
  (define dc (new svg-dc%
  [width width]
  [height height]
  [output filename]
  [exists exists]))
  (send dc start-doc "An SVG Test")  ; a message
  (send dc start-page)
  (draw-pict p dc 0 0)
  (send dc end-page)
  (send dc end-doc))



(save-pict-as-svg p 300 300 "output.svg")


2017-10-23 21:04 GMT+02:00 Lawrence Bottorff :

> I'd like to use Racket to generate scalable (svg?) graphics like gnuplot
> or GeoGebra does. For example, I'd like to create a cartesian coordinate
> graph system, then draw functions on it. One thing in particular would be
> to draw a graph of a circle based on the standard form of a circle, e.g.,
> x^2 + y^2 = r^2. Again, I'd prefer being able to create an svg file. Is
> there a tutorial that might give me more insight than the reference pages
> or the Quick: An Introduction to Racket with Pictures? Or am I barking up
> the wrong tree?
>
> LB
>
> --
> You received this message because you are subscribed to the Google Groups
> "Racket Users" group.
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> email to racket-users+unsubscr...@googlegroups.com.
> For more options, visit https://groups.google.com/d/optout.
>



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-- 
Jens Axel Søgaard

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[racket-users] Science graphics with Racket?

[Lawrence Bottorff]

I'd like to use Racket to generate scalable (svg?) graphics like gnuplot or
GeoGebra does. For example, I'd like to create a cartesian coordinate graph
system, then draw functions on it. One thing in particular would be to draw
a graph of a circle based on the standard form of a circle, e.g., x^2 + y^2
= r^2. Again, I'd prefer being able to create an svg file. Is there a
tutorial that might give me more insight than the reference pages or the
Quick: An Introduction to Racket with Pictures? Or am I barking up the
wrong tree?

LB

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[racket-users] Changing code fonts and turning off Unicode replacement in Scribble LaTeX output?

[David Christiansen]

Hi all,

I'm working on a set of lecture notes in Scribble, and the code blocks
contain identifiers that are Greek letters (namely, capital gamma and
lowercase rho). I'd like to render a pretty PDF as well as HTML output.
In the resulting LaTeX, however, the code includes things like
\RktSym{$\lambda$} and \RktVar{$\Gamma$}, which causes these
identifiers to be displayed using the math font instead of the
monospace code font, causing them to stick out like a sore thumb. I've
tested it by manually editing the file to put the Unicode names back
in, and the PDF looks fine coming out of both XeLaTeX and LuaLaTeX. 

I can certainly rig up a hacky Makefile to postprocess the output a
bit, but it would be nice to have a more elegant solution. Is there a
better way to configure the Unicode replacement?

Relatedly, I'd like to customize the TeX monospace font to one that I
happen to know contains lots of Unicode, and that I like the looks of.
As far as I can tell, declaring a TeX prefix at the command line will
blow away all of scribble/manual, while I just want to insert 2 lines.
The best I've been able to do so far is to add:

@(require scribble/core
  scribble/html-properties
  scribble/latex-properties)

@(define mycode
   (make-style "mycode"
   (list (make-tex-addition "mycode.tex"

to the top of the main document that includes all the sections, and
then 

@elem[#:style mycode]{}

somewhere to get the style included. mycode.tex contains:

\usepackage{fontspec}
\setmonofont{PragmataPro}
\newcommand*{\mycode}[1]{}

I'm not particularly concerned about compatibility with old-school
pdflatex here.

Is there a more elegant way to cause some LaTeX code to appear in the
preamble?

Thanks!

/David

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Re: [racket-users] proposed doc fix?

[Robby Findler]

The code is in drracket/private/tools.rkt; I think that that value
(the thing inside the outer listof) ends up in the `spec` field of an
`installed-tool` field and my read of the code suggests that it should
be (or/c string? (listof string?)), but I'm not completely confident
in that.

Robby


On Sun, Oct 22, 2017 at 10:11 PM, 'John Clements' via Racket Users
 wrote:
> The documentation currently states:
>
> "When DrRacket starts up, it looks for tools by reading fields in the 
> info.rkt file of each collection and the newest version of each PLaneT 
> package installed on the system. (Technically, DrRacket looks in a cache of 
> the "info.rkt" files contents created by raco setup. Be sure to re-run raco 
> setup if you change the contents of the info.rkt files). DrRacket checks for 
> these fields:
> • drracket-tools: (listof (listof string [subcollection-name]))
>
> • drracket-tool-names: (listof (or/c #f string))
> “
>
> I think this should instead be
>
> • drracket-tools: (listof (list/c string [subcollection-name]))
>
> …where the inner ‘listof’ is replaced by ‘list/c’. Is this correct? If so, I 
> can make a pull request.
>
> John Clements
>
>
>
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Re: [racket-users] Can anyone help me with a change?

[Josh Paley]

John,

If your name is ever submitted for sainthood, I'll sign the documents.

Many thanks from a grateful teacher!  (Now I need to learn how to do this
stuff myself...)

Regards,

Josh

On Sun, Oct 22, 2017 at 8:58 PM, John Clements 
wrote:

> Okay, this might now be done. You should be able to install it using
>
> raco pkg install simply-scheme
>
> OR you can use the package manager from within DrRacket.
>
> MAJOR disclaimer: I am not a user of Simply Scheme, and this package does
> not appear to include any tests.
>
> However, it appears that
>
> (+ “40” 2)
>
> does evaluate to 42, and
>
> (random 34)
>
> evaluates to different numbers on subsequent runs. That’s about all I know
> to test ….
>
> Let me know if you have any questions or problems with it.
>
> John Clements
>
> (and now I’m yet another hour behind on my grading… If only I still had an
> advisor to tell me to stop wasting time on these things.)
>
> > On Oct 22, 2017, at 18:50, Josh Paley  wrote:
> >
> > While I appreciate the level of detail that Stephen provided, I am
> absolutely slammed and don't know github usage, so what looks smallish to
> you (and probably would be for me if I were better educated on the system)
> is looking mighty large to me.  In terms of the fix, what needs to change
> is that there is code in simply.scm that needs to be commented out;
> everything else remains as it originally was.  And the code is actually
> documented within simply.scm: it says to remove the RANDOM code if the
> underlying interpreter supports it (which is the case here) and that's it.
> >
> > The version of Scheme this was designed for was at UC-Berkeley.  It
> wouldn't surprise me if there was some common ground with MIT Scheme, but I
> don't know for sure.
> >
> > I do plan to learn github at some point, but I'm kind of stuck at the
> moment.  If it only took an evening from where I am right now, I'd do this,
> but my lack of familiarity with the overall system has me very
> uncomfortable.
> >
> > On Sun, Oct 22, 2017 at 1:49 PM, Robby Findler <
> ro...@eecs.northwestern.edu> wrote:
> > On Sun, Oct 22, 2017 at 3:34 PM, Stephen De Gabrielle
> >  wrote:
> > > I don’t think packages on PLaneT can be updated but I may be wrong.
> >
> > They can be updated, but I would recommend that, instead of updating
> > them, you move them to pkgs, as Stephen suggests.
> >
> > (Of course, if you know people are using them and they cannot easily
> > change your code, please do update the planet version! But in any
> > other situation, I'd recommend abandoning them.)
> >
> > Robby
> >
> >
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