[racket] Lazy syntax class attributes

From: Eric Dobson (eric.n.dobson at gmail.com)
Date: Sat Jun 1 11:55:26 EDT 2013

I would say not to implement this just on my behalf. I think it would
be weird for pattern variables to act differently if they came from
syntax-parse versus from with-syntax.

On Fri, May 31, 2013 at 2:17 PM, Sam Tobin-Hochstadt <samth at ccs.neu.edu> wrote:
> On Fri, May 31, 2013 at 4:42 PM, Ryan Culpepper <ryanc at ccs.neu.edu> wrote:
>> Note, however, that the syntax class now uses #:attr instead of #:with.
>> That's the main usability issue I'm worried about with this change.
>> Following with-syntax's lead, a #:with clause automatically converts its
>> right-hand side to syntax---even if the result is "3D". That means that if
>> you forget that step of the conversion to laziness, you'll probably get
>> bizarre 3D syntax. I could change #:with to raise an error in some/all 3D
>> cases, but that might break existing programs.
>> Is anyone out there using syntax-parse to make 3D syntax?
> I'm sure all the places where I do this are bugs (and it has happened
> to me), so I'd welcome this error.
> Sam

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