(module scheme.r5rs ()

  (import chicken)
  (import
   (rename scheme
	   (null-environment %null-environment)
	   (scheme-report-environment %scheme-report-environment)))

  (import numbers)
  (export angle make-polar make-rectangular rationalize)

  (require-extension scheme.eval)
  (export null-environment scheme-report-environment)

  (reexport
   (except scheme
	   null-environment scheme-report-environment eval
	   and begin begin-for-syntax case cond cond-expand
	   define define-syntax delay delay-force do export if
	   import import-for-syntax lambda let let* let-syntax
	   letrec letrec* letrec-syntax module or quasiquote quote
	   reexport require-extension require-extension-for-syntax
	   require-library set! syntax syntax-rules))

  (define-constant null-environment-identifiers
    '(and begin case cond cond-expand define define-syntax delay
      delay-force do if lambda let let* let-syntax letrec letrec*
      letrec-syntax or quasiquote quote set! syntax-rules))

  (: null-environment (fixnum -> (struct environment)))

  (define (null-environment version)
    (case version
      ((7)  (environment `(only (scheme base) ,@null-environment-identifiers)))
      ((5)  (environment `(only (scheme r5rs) ,@null-environment-identifiers)))
      (else (%null-environment version))))

  (: scheme-report-environment (fixnum -> (struct environment)))

  (define (scheme-report-environment version)
    (case version
      ((7)  (environment '(scheme base)))
      ((5)  (environment '(scheme r5rs)))
      (else (%scheme-report-environment version)))))