On Fri, May 20, 2011 at 3:39 PM, Matthias Felleisen <matth...@ccs.neu.edu> wrote: > > > Let me make my proposals (2 and 3) more precise because your response > suggests they were too short. > > 1. We could make internal define the primary vehicle for definitions, i.e., > not compile thru letrec. As far as I am concerned, your change to the > language to allow defines in many more places has made letrec superfluous. > > 2. The semantics for internal defines would be more Algol like, meaning your > example would immediately behave like let and thus be fast. > > 3. As far as letrec is concerned, we can make it 'expensive' if it is no > longer the intermediate target instruction from the macro compiler's > perspective. > > -- I think my preferred solution would be to wrap letrec so that > continuations grabbed during the setup set up a continuation mark that labels > them as 'dangerous'. When you reinvoke them, the existence of the mark tells > you that the reference cells should be reinitialized (probably only the ones > on the control flow from the continuation point).
Why do you prefer this to putting a prompt around the rhs of each letrec binding? Robby _________________________________________________ For list-related administrative tasks: http://lists.racket-lang.org/listinfo/dev
