At Mon, 10 Oct 2011 10:09:49 -0700 (PDT), michael rice wrote: > I'm looking at some old Scheme code and find that the code still > works under (#lang racket) but trace is unhappy with the use of set! > in the traced function. > > set!: cannot modify a constant: next-leaf-generator
I added `(trace next-leaf-generator)' to your code, and everything ran fine. What exactly did you try adding to the code you included? Also, which version of Racket are you using? > I also tried (#lang r5rs) but it's unhappy with my require. > > (require racket/trace) => expand: unbound identifier in module in: require `#lang r5rs' is R5RS, and pretty much nothing else, so no `require'. You can work around it by using `#%require'. Using `#lang racket' is usually the right thing to do instead. Vincent _________________________________________________ For list-related administrative tasks: http://lists.racket-lang.org/listinfo/users
