private-namespace.scm

;;;; compiler-namespace.scm - A simple namespace system to keep compiler variables hidden
;
; Copyright (c) 2008-2015, The CHICKEN Team
; Copyright (c) 2007, Felix L. Winkelmann
; All rights reserved.
;
; Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following
; conditions are met:
;
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;     disclaimer. 
;   Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following
;     disclaimer in the documentation and/or other materials provided with the distribution. 
;   Neither the name of the author nor the names of its contributors may be used to endorse or promote
;     products derived from this software without specific prior written permission. 
;
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(define-syntax private
  (er-macro-transformer
   (lambda (form r c)
     (let ((namespace (cadr form))
	   (vars (cddr form)))
       (##sys#check-symbol namespace 'private)
       (let* ((str (symbol->string namespace)) ; somewhat questionable (renaming)
	      (prefix (string-append 
		       (string (integer->char (string-length str)))
		       (symbol->string namespace))))
	 (for-each
	  (lambda (var)
	    (put! 
	     var 'c:namespace
	     (##sys#string->qualified-symbol prefix (symbol->string var))))
	  vars)
	 '(##core#undefined) ) ) ) ) )

(set! ##sys#alias-global-hook
  (lambda (var . assign)		; must work with old chicken
    (or (get var 'c:namespace) var) ) )