[racket-dev] Dotted syntax/parse patterns and scribble/eval

From: Carl Eastlund (cce at ccs.neu.edu)
Date: Fri Sep 23 09:17:12 EDT 2011

On Wed, Sep 21, 2011 at 7:44 PM, Ryan Culpepper <ryan at cs.utah.edu> wrote:
> This particular bug only affects patterns of the form
>  (<stuff> . var:expr)
> If you've seen pattern variables get non-syntax values in some other way,
> please let me know! (BTW, by "pattern variable" I mean a name bound directly
> in the pattern; "nested attributes" like var.value are allowed to contain
> non-syntax values.)

...except for pattern variables nested under ellipses, which are bound
to lists; or pattern variables bound under ~or patterns, or under
~optional without #:defaults, which may be bound to #false.  Right?
And I assume by "pattern variable" you are excluding the ~bind action
pattern, the #:attr pattern directive, and the #:defaults clause of
~optional, all of which may supply arbitrary values; presumably those
are "attributes" but not "pattern variables" per se.


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