Does this get you what you want?
#lang racket
(require (for-syntax syntax/parse racket/syntax))

(define-syntax (define-stuff stx)
 (syntax-parse stx
   [(_ attr-name macro-name)
    #:with c.attr-name (format-id #'c "~a.~a" #'c #'attr-name)
    #'(begin
        (begin-for-syntax
          (define-syntax-class C
            (pattern any #:attr attr-name #'any)))
        (define-syntax macro-name
          (syntax-parser
            [(_ (~var c C))
             #'c.attr-name])))]))
(define-stuff an-attr a-macro)
(a-macro 1)


On Aug 21, 2015, at 12:57 PM, Stephen Chang <stch...@ccs.neu.edu> wrote:

> Is there a way to access an attribute, other than with the "." syntax?
> 
> For example, the following example does not work:
> 
> #lang racket
> (require (for-syntax syntax/parse))
> 
> (define-syntax (define-stuff stx)
>  (syntax-parse stx
>    [(_ attr-name macro-name)
>     #'(begin
>         (begin-for-syntax
>           (define-syntax-class C
>             (pattern any #:attr attr-name #'any)))
>         (define-syntax macro-name
>           (syntax-parser
>             [(_ (~var c C))
>              #'c.attr-name])))]))
> (define-stuff an-attr a-macro)
> (a-macro 1)
> 
> I've also tried various format-id's which I also can't get to work. Is
> there an alternate way, in the spirit of ~var vs ":", to get an
> attribute's value?
> 
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