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

From: Filipe Cabecinhas (filcab at gmail.com)
Date: Thu Jun 19 16:46:09 EDT 2008

On 19 Jun, 2008, at 16:37, 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?

Are you trying to trace a required function? I think you can't change  
identifiers that were required.
Could we know what function are you tracing and how you get that  

   - Filipe Cabecinhas

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