On Thu, May 23, 2013 at 2:29 PM, Matthias Felleisen <matth...@ccs.neu.edu> wrote: > > 1. At some point, we had a macro that opened up modules and made all > module-level identifiers available. Wouldn't a flavor of this macro work here > and, if so, wouldn't it be cheaper? Or is this what you call dumpster-diving, > traversing the expansion and extracting ids from there?
You're probably thinking of `require/expose`. This isn't the same feature, because it gives you the right value, but not the right identifier. But it works similarly to the way the code Eric posted now works, using namespaces explicitly. > > 2. Is it possible that we could solve the problem via a bootstrapping-only > violation of our policy that you can add types to Racket w/o modifying > existing modules? No. We can't specify types inside `racket/base` without making `racket/base` depend on Typed Racket. Sam > > > > > > > > > On May 23, 2013, at 9:22 AM, Sam Tobin-Hochstadt <sa...@ccs.neu.edu> wrote: > >> On Thu, May 23, 2013 at 1:54 PM, Matthias Felleisen >> <matth...@ccs.neu.edu> wrote: >>> Can you raise the level of discourse one level and perhaps figure out >>> whether this is needed at all? I.e., find a different way to solve the >>> problem? (What is the real problem?) >> >> This is important, and it's the second implementation of this feature. >> The previous one was substantially more painful, and involved >> local-expand and "dumpster-diving". >> >> The reason we need a tool like this is that the expansion of some >> macros (examples include `for`, `delay`, `quasiquote`, among others) >> have runtime support functions that are not exported. Typed Racket >> needs to specify the type of these operations. You can see these >> specifications here: >> https://github.com/plt/racket/blob/master/collects/typed-racket/base-env/base-special-env.rkt >> . That means that it needs to construct those identifiers, although it >> never needs to execute code with those identifiers. >> >> The previous implementation was much slower here, remarkably. >> >> Sam > _________________________ Racket Developers list: http://lists.racket-lang.org/dev
