Does `identifier-binding` not give you the symbol that you need?
At Wed, 16 Jul 2014 23:32:46 -0400, Sam Tobin-Hochstadt wrote: > Ok, I thought I had figured this out, but I was wrong. > > Here's what I want to be able to do: > > - take an identifier in a fully-expanded source file > - translate that identifier to some symbol in a predictable way > - so that other references to that same (free-identifier=?) > identifier get translated to the same symbol > > It's pretty easy to do this in a single module -- just keep a > free-id-table of all the identifiers mapping to gensyms. But I want to > be able to do this across modules, and across invocations of this > program. IOW, when I run my program on one source file, I'd like to > get a symbol for a provided definition that's the same symbol I get > when I run my program on a different source file containing a > reference to that definition. > > Clearly this is possible, since Racket manages, but is there a way > that I can do it? > > Sam > > On Wed, Jul 16, 2014 at 7:55 AM, Matthew Flatt <mfl...@cs.utah.edu> wrote: > > Yes, it can be ".2", etc. The numbers are generated as needed to create > > distinct names --- deterministically for a given module compilation, > > assuming that all macros used by expansion are deterministic. > > > > At Wed, 16 Jul 2014 07:36:50 -0400, Sam Tobin-Hochstadt wrote: > >> Does that mean that I can/should just drop the .1 to get the defined name? > >> Can it also be .2 etc? > >> > >> Sam > >> On Jul 16, 2014 4:34 AM, "Matthew Flatt" <mfl...@cs.utah.edu> wrote: > >> > >> > That `posn1.1` is a unreadable symbol that stands for the symbol > >> > `posn1` plus some marks that distinguish it. > >> > > >> > In other words, `posn1.1` bridges (in an ugly way) the symbol-based > >> > world of module environments and the identifier-based world of syntax. > >> > In the future, I hope to shift module environments to be > >> > identifier-based to avoid these unreadable symbols. > >> > > >> > At Tue, 15 Jul 2014 09:10:26 -0400, Sam Tobin-Hochstadt wrote: > >> > > If you take this program and fully-expand it in the macro stepper: > >> > > > >> > > #lang racket > >> > > (struct posn (x y)) > >> > > (define p1 (posn 1 2)) > >> > > > >> > > You see that the residual program has an application of the `posn1` > >> > > function, which is the hidden constructor. And indeed, the > >> > > fully-expanded program has a definition of `posn1`. However, if you > >> > > click on the use of `posn1`, the macro stepper will tell you that it's > >> > > defined in this module as `posn1.1`, and provided as `posn1.1` as > >> > > well. If you write program to grovel through the fully-expanded > >> > > syntax, you get these same results as the `src-id` and > >> > > `nominal-src-id` from `identifier-binding`. > >> > > > >> > > Why is this? And is there a way to get from `posn1.1` to `posn1` > >> > reliably? > >> > > > >> > > Sam > >> > _________________________ Racket Developers list: http://lists.racket-lang.org/dev
