[plt-scheme] A macro for declaring class properties, a question

From: Grant Rettke (grettke at acm.org)
Date: Thu Oct 18 11:43:51 EDT 2007

On 10/18/07, Matthias Felleisen <matthias at ccs.neu.edu> wrote:
> Hygiene means create names to avoid binding conflicts. So in this case,
> imagine that each use of (property name) would actually introduce
> super-secret-name1, super-secret-name2, etc. See macro stepper.

In the case of Noel's code, then:

(define-syntax property
 (syntax-rules ()
   [(_ name)
    (begin (field super-secret-field-name)
           (define/public name
               [() super-secret-field-name]
               [(value) (set! super-secret-field-name value)])))]))

Hygiene would avoid name clashes if all of the properties are
generated within that macro: think (property x y z) versus (property
x) (property y) (property z). Otherwise super-secret-field-name would
get generated 3 times? I think this is the case as I just tried out
the latter and got name clashes.

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