> On Dec 14, 2016, at 7:14 AM, Matthew Flatt <mfl...@cs.utah.edu> wrote: > > To summarize, don't try to attach syntax objects as property values > like that. I know this advice sounds ironic, given that the original > use of properties was for syntax-valued keys like 'origin. Properties > like 'origin are meant to be extracted from just-expanded programs, > though, as opposed to used in a later compilation step. At the same > time, those uses of properties are why we can't just make > `syntax-property` reject property values that are syntax objects.
What are the implications of this for the Types as Macros/Turnstile stuff that Stephen and Alex have been working on, given that they use heavily use syntax objects in syntax properties as part of attaching type information to identifiers? Are they doing something to work around this and/or using properties in a way that avoids this issue? Or is it likely that they’ll run into this for programs that span multiple modules? (Obviously, I have a personal motive for asking this question, since I’ve been playing with Turnstile and the techniques it uses myself. So far I’ve been able to write programs that span multiple modules without much issue, modulo an issue I asked about on this mailing list a month or two back, but I’d like to know if I’m relying on some sort of undefined behavior.) -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
