[plt-scheme] syntax identifier used out of context

From: Jon Rafkind (rafkind at cs.utah.edu)
Date: Thu Dec 11 02:21:49 EST 2008

I'm wondering why I get this error from the following code. I was 
helping someone on IRC so I don't have a real use case, just wondering 
what the error means. If I change bar2 to bar in the template then it 
works. Also it seems like I should be able to replace the lambda in 
syntax-parameterize by just bar2, but then I get an error about bar2 not 
being bound in the transformer environment.

 > compile: identifier used out of context in: bar2

#lang scheme

(require scheme/stxparam)

(define-syntax-parameter x (lambda (stx) (error "dont use x")))

(define-syntax bar
  (syntax-rules ()
    ((_ q) (+ 1 q))))

(define-syntax (foo stx)
  (define (bar2 stx3)
    (syntax-case stx3 ()
      ((_ q) #'(+ 1 q))))
  (syntax-case stx ()
    ((_ pat) #'(syntax-parameterize ([x (lambda (stx3)
                                          (syntax-case stx3 ()
                                             ((_ . q) #'(bar2 . q)))) ])
                     (printf "You won ~a!\n" pat))))))

(foo (x 4))

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