;; (param) => get-cell + cdr
;; (param value) => get-cell + [convert] + set-cdr!

;; need 3 opcodes: param cell
;;                 context params
;;                 context-params-set!

;; analyze needs to translate param calls to proper usages of the
;; first two opcodes

;; (parameterize ((param value)) body ...)
;;  => (let* ((old-params (thread-parameters))
;;            (new-params (cons (cons param (param-convert value)) old-params)))
;;       (dynamic-wind (lambda () (thread-set-parameters! new-params))
;;                     (lambda () body ...)
;;                     (lambda () (thread-set-parameters! old-params))))

(define-module (srfi 39)
  (export make-parameter parameterize)
  (import-immutable (scheme))
  (include-shared "39/param")
  (include "39/syntax.scm"))