[plt-scheme] plt-scheme 4.0 error - set!: cannot modify a constant:

That worked, thank you.


--- On Fri, 20/6/08, Chongkai Zhu <czhu at cs.utah.edu> wrote:

> From: Chongkai Zhu <czhu at cs.utah.edu>
> Subject: Re: [plt-scheme] plt-scheme 4.0 error - set!: cannot modify a constant:
> To: doolagarl2002 at yahoo.com.au
> Cc: plt-scheme at list.cs.brown.edu
> Received: Friday, 20 June, 2008, 2:11 AM
> I don't think this is about v4.
> 
> In v3xx, you use the MzScheme langauge (or similar), and do
> trace in the 
> REPL, which is all fine
> 
> In v4 now, you are using the module language (#lang scheme,
> or similar), 
> and still want to do the trace in REPL, which is not
> allowed.
> 
> Just move your
> 
> (require (lib "trace.ss"))
> (trace foo)
> 
> lines into the body of the module will solve the problem.
> 
> Chongkai
> 
> 
> Scott Brown wrote:
> > In earlier versions of plt-scheme I could trace
> functions like this:
> >
> > (require (lib "trace.ss"))
> > (trace foo)
> >
> > But in plt-scheme 4.0 this gives an error:
> >
> > set!: cannot modify a constant: foo
> >
> > How can I fix this?
> >
> >
> >       Get the name you always wanted with the new
> y7mail email address.
> > www.yahoo7.com.au/mail
> > _________________________________________________
> >   For list-related administrative tasks:
> >   http://list.cs.brown.edu/mailman/listinfo/plt-scheme
> >


      Get the name you always wanted with the new y7mail email address.
www.yahoo7.com.au/mail