[racket] Question on error message

Alvin,

This looks like a bug in errortrace, one of the compiler extensions
DrRacket uses to provide debugging information at runtime.  Here's a
workaround you can use:

  1. Open the "Language" menu.
  2. If there is no right-hand pane to the menu, click the "Show Details"
button in the lower left.
  3. On the top right of the menu, in the "Dynamic Properties" group,
select "No debugging or profiling".
  4. Click "OK".

After that, running your program should work.  I've tested this with Racket
version 5.3.6 and with a recent git checkout.  We would also really
appreciate it if you could report this bug using "Submit Bug Report..." in
the Help menu of DrRacket.  Thanks very much, sorry for the bug!

Carl Eastlund

On Fri, Sep 6, 2013 at 9:22 AM, Alvin Schatte <AlvinSchatte at skytex.net>wrote:

>   Hello Carl,
>
> I found a location in mras.rkt where I comment out the provide for the
> map-2 function, the program runs, and when I re-instate it, it fails.  The
> section of code is:
>
> ;;  map-2
> (provide
> (proc-doc/names map-2
>                  (procedure? list? list? . -> . list?)
>                  (proc l1 l2)
>                  @{Applies a procedure of two elements to the elements of
> two lists,
>                    @racket[l1] and @racket[l2], returning the result in
> another list.
>                    When one list is exhausted, the other list is returned
> as the rest of the resultant list.}))
>
> Also, when the proc-doc/names section is replaced by the function name,
> i.e., (provide map-2), the program runs.
>
> I was removing provide contracts one by one to see if I could find the
> problem.  Fortunately, it occurred on the first one I tried, but I don’t
> know why.
> Thanks for your help.  I am interested in knowing why this problem occurs,
> if you are able to diagnose it further.
> Alvin Schatte
>
>  *From:* Carl Eastlund <cce at ccs.neu.edu>
> *Sent:* Wednesday, September 04, 2013 9:38 PM
> *To:* Alvin Schatte <AlvinSchatte at skytex.net>
> *Cc:* Racket Users <users at racket-lang.org>
> *Subject:* Re: [racket] Question on error message
>
>    Alvin,
>
> Thanks for the source.  Unfortunately, I can't run what you sent because
> it's missing at least one file.  Try the following when sharing code for
> debugging purposes:
>
> 1. Use a site like pastebin.com or gist.github.com where you can easily
> paste and share a file without copying an attachment to many people's
> inboxes over a mailing list.
> 2. Include all necessary files, or better yet reduce the example to one
> file.
> 3. Similarly, reduce dependencies on third-party libraries such as planet
> packages if possible.
>
> Right now I'm missing "diff-e solver.rkt" and I have to install
> "wmfarr/simple-matrix:1:1", which is doable but inconvenient.  Thanks for
> the question and followup, and I'm happy to help if you can post a complete
> example.
>
>  Carl Eastlund
>
> On Wed, Sep 4, 2013 at 10:22 PM, Alvin Schatte <AlvinSchatte at skytex.net>wrote:
>
>>   Hello Carl,
>> Thank you for looking at this.  I am writing contracts and playing with
>> documentation for a fairly large module that, right now, performs a system
>> identification function.  The file is attached.  I made several changes
>> without “Run”ning, so I’m not sure what changed caused the error.
>> Thank you again for your help,
>> Alvin Schatte
>>
>>  *From:* Carl Eastlund <cce at ccs.neu.edu>
>> *Sent:* Wednesday, September 04, 2013 9:06 PM
>> *To:* Alvin Schatte <AlvinSchatte at skytex.net>
>> *Cc:* Racket Users <users at racket-lang.org>
>> *Subject:* Re: [racket] Question on error message
>>
>>   Alvin,
>>
>> That looks like an internal error message from some language feature
>> you're using, unless you're using something like begin-lifted or
>> syntax-local-lift-expression directly.  Often the contract system generates
>> names for internal use like "lifted.171", but there shouldn't be duplicate
>> definitions, and if there are, it's likely not your fault.  Can you share
>> the code that causes this error message?  If so, someone may be able to
>> diagnose the error.  Otherwise, with just the error message, we don't have
>> much to go on.
>>
>> Carl Eastlund
>>
>> On Wed, Sep 4, 2013 at 9:59 PM, Alvin Schatte <AlvinSchatte at skytex.net>wrote:
>>
>>>   Hello,
>>> I got the following error message after <Ctrl-R> in Dr. Racket.  I am
>>> not sure what  it means:
>>>
>>> module: duplicate definition for identifier in: lifted.171
>>>
>>> Could someone explain it to me?
>>> Alvin Schatte
>>>
>>> ____________________
>>>   Racket Users list:
>>>   http://lists.racket-lang.org/users
>>>
>>>
>>
>> No virus found in this message.
>> Checked by AVG - www.avg.com
>> Version: 2013.0.3392 / Virus Database: 3222/6639 - Release Date: 09/04/13
>>
>
>
> No virus found in this message.
> Checked by AVG - www.avg.com
> Version: 2013.0.3392 / Virus Database: 3222/6639 - Release Date: 09/04/13
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.racket-lang.org/users/archive/attachments/20130906/8ce44b1a/attachment.html>