; Syntax-rules functions
; Copyright 2005 Brian Alliet

; Oleg's syntax-rules version of symbol? from comp.lang.scheme
; Copyright 2003 Oleg Kiselyov
; Message ID: 7eb8ac3e.0309301103.5200afbf@posting.google.com
(define-syntax symbol??
  (syntax-rules ()
    ((symbol?? (x . y) kt kf) kf)	; It's a pair, not a symbol
    ((symbol?? #(x ...) kt kf) kf)	; It's a vector, not a symbol
    ((symbol?? maybe-symbol kt kf)
      (let-syntax
	((test
	   (syntax-rules ()
	     ((test maybe-symbol t f) t)
	     ((test x t f) f))))
	(test abracadabra kt kf)))))

; syntax-error is used to throw an error from a syntax-rule
; A call to syntax-error with args will not match any rules below and most Scheme implmentations
; will display the call and the arguments (which should contain some helpful error message)
(define syntax-error
    (syntax-rules ()
        ((syntax-error) (syntax-error "call me with args!"))))