[racket-users] Strange Error (Take 2)

I am getting strange error in my Racquel package unit tests. I'm not sure what Racket release it started appearing in, but certainly 6.6 or 6.5. A couple of days ago, I posted the all of code that was causing the error, but there was too much going on for anyone to make sense of it (including

Re: [racket-users] Good parser library in Racket

Thanks John and Jens! Regards, Kashyap On Sat, Oct 1, 2016 at 11:23 AM, Jens Axel Søgaard wrote: > Take a look at: > > http://planet.racket-lang.org/display.ss?package=java. > plt=dherman > > 2016-10-01 20:00 GMT+02:00 C K Kashyap : > >> Hi

Re: [racket-users] Scribble: how to use #:tag-prefix and have @elemref work within the Table Of Contents?

I've pushed a repair and also corrected the contracts on `elemtag` and `elemref` to allow taglets. When content is lifted to the table of contents, it was rendered as being in the page's part, and opposed to the part where the content originated. I've fixed ToC rendering for this this case,

Re: [racket-users] Contract violation where number expected - can't understand why

On Sat, 01 Oct 2016 15:44:18 -0500, Angus wrote: > > And it is now more obvious to me that in: > > (define (bigger w) > (interval (min (interval-big w) > (add1 (guess w))) > (interval-big w) (+ (interval-guesses w) 1))) > > The (interval... part is a constructor

Re: [racket-users] Contract violation where number expected - can't understand why

On Saturday, 1 October 2016 16:13:01 UTC+1, Ben Greenman wrote: > Maybe this will help: > > > > > (struct interval (small big guesses)) > > creates 5 new functions > interval, for making intervals. For example (interval 5 10 0) creates an > interval from 5 to 10 that has 0 guessesinterval?,

Re: [racket-users] Good parser library in Racket

Take a look at: http://planet.racket-lang.org/display.ss?package=java.plt=dherman 2016-10-01 20:00 GMT+02:00 C K Kashyap : > Hi Racket users, > It appears that parser-tools/yacc is the parser tool that's bundled with > racket by default. I'd like to parse java like

[racket-users] Re: Good parser library in Racket

On Saturday, October 1, 2016 at 2:00:23 PM UTC-4, ckkashyap wrote: > Hi Racket users, > It appears that parser-tools/yacc is the parser tool that's bundled with > racket by default. I'd like to parse java like language. I was wondering if > there is already such an implementation that I could

[racket-users] Good parser library in Racket

Hi Racket users, It appears that parser-tools/yacc is the parser tool that's bundled with racket by default. I'd like to parse java like language. I was wondering if there is already such an implementation that I could use or perhaps a reference implementation I could use. The example in the

Re: [racket-users] Strange Error Message

Hi Scott, I think that you're seeing a bug in the current expander's marshaling of information for a compiled module, specifically for the "metadata.rkt" module that supplies `racquel-namespace`. (The bug was introduced in v6.3 with the set-of-scopes expander. Happily, a re-implementation of the

Re: [racket-users] Contract violation where number expected - can't understand why

Maybe this will help: (struct interval (small big guesses)) creates 5 new functions 1. interval, for making intervals. For example (interval 5 10 0) creates an interval from 5 to 10 that has 0 guesses 2. interval?, for testing if a value is an interval. For example (interval? 1) is

Re: [racket-users] Contract violation where number expected - can't understand why

On Sat, 01 Oct 2016 09:47:00 -0500, Angus wrote: > I don't understand. How would I pass it an interval? > > I am confused about the w parameter in smaller. ie (define (smaller w) > > what is w? Is that the current interval held as state within big-bang? Yes, that is correct. Have a closer

Re: [racket-users] Contract violation where number expected - can't understand why

I guess you're familiar with the dot operator (object.field) in C and Java? In Racket, we don't provide access to that directly, but instead put such operations in "selector functions". So when you see (interval-guesses w) that's something more like w.guesses In other words, you can think

Re: [racket-users] Contract violation where number expected - can't understand why

On Saturday, 1 October 2016 15:30:19 UTC+1, Vincent St-Amour wrote: > On Sat, 01 Oct 2016 09:13:25 -0500, > Angus wrote: > > Then I changed smaller (and bigger) like this: > > > > (define (smaller w) > > (interval (interval-small w) > > (max (interval-small w) > >

Re: [racket-users] Contract violation where number expected - can't understand why

On Saturday, 1 October 2016 15:30:19 UTC+1, Vincent St-Amour wrote: > On Sat, 01 Oct 2016 09:13:25 -0500, > Angus wrote: > > Then I changed smaller (and bigger) like this: > > > > (define (smaller w) > > (interval (interval-small w) > > (max (interval-small w) > >

Re: [racket-users] Contract violation where number expected - can't understand why

On Sat, 01 Oct 2016 09:13:25 -0500, Angus wrote: > Then I changed smaller (and bigger) like this: > > (define (smaller w) > (interval (interval-small w) > (max (interval-small w) > (sub1 (guess w) > > to > > (define (smaller w) > (interval (interval-small

Re: [racket-users] Realm of Racket chapter 5 easy question variable update question

> On Oct 1, 2016, at 7:51 AM, Greg Trzeciak wrote: > > On Saturday, October 1, 2016 at 11:35:52 AM UTC+2, Angus wrote: >> 2. I don't really understand what is happening with the big-bang on-tick. >> >> My background is imperative languages, eg C, C++, Java, python, etc.

[racket-users] Re: Realm of Racket chapter 5 easy question variable update question

On Saturday, October 1, 2016 at 11:35:52 AM UTC+2, Angus wrote: > 2. I don't really understand what is happening with the big-bang on-tick. > > My background is imperative languages, eg C, C++, Java, python, etc. Not > sure if that helps. Coming from OOP background following tutorial may be

Re: [racket-users] Realm of Racket chapter 5 easy question variable update question

Hi Angus, 2. I don't really understand what is happening with the big-bang on-tick. > The big-bang function is passed 50 as the initial state. Does the big-bang > function somehow internally keep the state variable cached and then it gets > updated by the change-state function. That bit seems a

[racket-users] Re: Require/typed with racket/tcp

On Saturday, October 1, 2016 at 3:10:12 PM UTC+5:30, Sourav Datta wrote: > I am currently trying to use racket/tcp library in a TR program and used > require/typed to import the necessary functions as I could not find this > provided with TR by default. However, the following code has a problem

[racket-users] Require/typed with racket/tcp

I am currently trying to use racket/tcp library in a TR program and used require/typed to import the necessary functions as I could not find this provided with TR by default. However, the following code has a problem when it runs: #lang typed/racket (require/typed racket/tcp

[racket-users] Realm of Racket chapter 5 easy question variable update question

I am working through Realm of Racket chapter 5, last exercise was: Find an image of a locomotive and create an animation which wraps around to the left side of the screen after passing the right margin. I have a solution which is below, but have some questions: 1. Is the solution below a