I'm not really clear on what you're trying to do. One way to explain more might be to explain how `test` is meant to differ from `begin`. Or maybe you can say why it doesn't work to add the internal-definition context to the bindings listed in `exports` (i.e., to bring everything into the definition context).
At Mon, 05 Jan 2015 16:44:10 +0000, Spencer Florence wrote: > Is there any way to have the `test` macro work more like `begin`? > > What I am trying to accomplish is something like: > > (define-syntax (make-my-unit stx) > (syntax-parse stx > [(e ...) > (with-syntax ([body (local-expand/capture-lifts stx <something>)]) > #'(unit (imports ...) (exports ...) body))])) > > Where the defines in #'(e ...) are visible to `unit` so that they can be > used for exports. > > --spf > On Mon Jan 05 2015 at 11:32:46 AM Matthew Flatt <mfl...@cs.utah.edu> wrote: > > > I think it's more a question of what a definition context is supposed > > to be, rather than how `syntax-local-bind-syntaxes` works. > > > > When you create a new definition context, the context's bindings are > > visible only to expressions that are also in that context. The `test` > > form here creates a new definition context in much the same way as > > `(let () ...)`: > > > > (let () > > (let () (define x 1)) > > x) > > > > In other words, the final `x` really is out of the scope of the > > definition of `x`. > > > > At Mon, 05 Jan 2015 16:26:30 +0000, Spencer Florence wrote: > > > Progress is a new error! I don't think I understand how > > > syntax-local-bind-syntaxes is supposed to work. I extended the previous > > > program: > > > > > > #lang racket > > > (require (for-syntax syntax/parse)) > > > (define-syntax (test stx) > > > (syntax-parse stx > > > [(_ e) > > > (define ctx > > > (if (list? (syntax-local-context)) > > > (cons (gensym) (syntax-local-context)) > > > (list (gensym)))) > > > (define def-ctx (syntax-local-make-definition-context)) > > > (define expd (local-expand #'e ctx (list #'define-values) def-ctx)) > > > (define ids (syntax-parse expd [(def (id) _) (list #'id)])) > > > (syntax-local-bind-syntaxes ids #f def-ctx) > > > (internal-definition-context-seal def-ctx) > > > expd])) > > > (let () > > > (test (define x 1)) > > > x) > > > > > > And now I receive the error: `x: unbound identifier in module in: x` > > > Looking at the docs for `syntax-local-make-definition-context` it seems > > > like I need to provide it with the parent definition-context, but I'm not > > > sure how to get a hold of that. > > > > > > --spf > > > > > > On Mon Jan 05 2015 at 10:00:53 AM Matthew Flatt <mfl...@cs.utah.edu> > > wrote: > > > > > > > The error message is intended for "end users" and turns out to be > > > > misleading for the implementor of an internal-definition context. The > > > > documentation for `define-values` has essentially the same problem: it > > > > describes how `define-values` should work in an internal-definition > > > > context, but it doesn't say how the form interacts with `local-expand`. > > > > > > > > A `define-values` form will only expand in a module or top-level > > > > context. To implement an internal-definition context, you must expand > > > > only far enough to see `define-values` form; in other words, supply > > > > `#'define-values` in the stop list. Then, a partially expanded > > > > `define-values` form must be recognized and handled explicitly, with > > > > tools like `syntax-local-bind-syntaxes` or re-writing to > > > > `letrec-values`, as appropriate for the definition context. > > > > > > > > At Mon, 05 Jan 2015 14:49:03 +0000, Spencer Florence wrote: > > > > > Hey all, > > > > > > > > > > I'm trying to use 'local-expand', however it seems to think its > > never in > > > > a > > > > > definition context. For example: > > > > > > > > > > (require (for-syntax syntax/parse)) > > > > > (define-syntax (test stx) > > > > > (syntax-parse stx > > > > > [(_ e) > > > > > (define ctx > > > > > (if (list? (syntax-local-context)) > > > > > (cons (gensym) (syntax-local-context)) > > > > > (list (gensym)))) > > > > > (local-expand > > > > > #'e ctx null > > > > > ;; result is the same with this uncommented > > > > > #;(syntax-local-make-definition-context))])) > > > > > (let () > > > > > (test (define x 1)) > > > > > x) > > > > > > > > > > errors with a "define-values: not in a definition context in: > > > > > (define-values (x) 1)" > > > > > > > > > > Can anyone provide any insight into what is going on? > > > > > > > > > > --spf > > > > > ____________________ > > > > > Racket Users list: > > > > > http://lists.racket-lang.org/users > > > > > > ____________________ Racket Users list: http://lists.racket-lang.org/users
