I don't understand Matthias's performance comments. If, in TR (require plot) actually gives me a typed version of the library and in R (require plot) gives me the untyped version of the library, then I am avoiding the performance the untyped/typed performance overhead properly. If, on the other hand, if I have to commit that (require plot) gives me either the untyped or the typed version, then I have to suffer the performance overhead when I require it from the "wrong" context. Neil's original complaint also has validity, I think: if he provides a plot/typed today, and then later ports plot so it is typed, then he has to keep this extra thing around for what appears to not be a very good reason. And while I do understand Sam's reluctance to mess with module resolution, I think that just not solving this problem is worse. And finally (and perhaps this is the root of the problem), I cannot understand what TR actually does by reading its documentation. For example, the docs for 'require' do not explain why I can make a copy of "list.rkt" (in the racket collection), call the copy "listt.rkt" and have that copy not work, but the original one does. Clearly TR is not just "get[ting] *exactly* the same file as in R", so I think Sam's comments are off base.<div> Robby On Mon, Dec 17, 2012 at 2:51 PM, Sam Tobin-Hochstadt <<a href="mailto:samth@ccs.neu.edu">samth@ccs.neu.edu</a>> wrote: > > On Mon, Dec 17, 2012 at 3:27 PM, Robby Findler > <<a href="mailto:robby@eecs.northwestern.edu">robby@eecs.northwestern.edu</a>> wrote: > > I've long thought something along these lines is a good idea, but perhaps > > what I think is a good idea isn't what Matthias and Sam think is the bad > > idea. > > > > I think that it makes sense for 'require' in typed-racket to look in a > > different place than 'require' in untyped racket looks so that one can write > > the same require spec (in both the docs and the code) and have two versions > > of the same library, one that is typed and one that isn't typed. Then, then > > library writer, if they choose, can decide who pays what for going (or not) > > across the boundary between typed and untyped. (Or maybe submodules would be > > better.) > > I think this is exactly what Eli was suggesting, and what I think is a bad idea. > > > I think this is already happening in TR anyways, when I write > > > > (require racket/list) > > > > I don't get the same file being loaded when that is in a TR program as when > > it is in a R program. > > You get *exactly* the same file as in R. I think that (a) this is a > valuable invariant and (b) the mechanisms for violating this invariant > are all very worrying. > > Sam</div>