7491e172ea
The eopl language is now racket-based rather than mzscheme-based. This test-suite, which was originally distributed on the book's web-site has been re-written in the new language. Changes include dropping all drscheme-init.scm and top.scm files. Remaining files were renamed to use the .rkt extension and edited to use the #lang syntax (instead of modulue). Require and provide forms were changed to reflect racket's syntax instead of mzscheme's (eg, only-in vs. only). Several occurrences of one-armed ifs were changed to use when and unless. All tests have been run successfully.
84 lines
2.0 KiB
Racket
Executable File
84 lines
2.0 KiB
Racket
Executable File
#lang eopl
|
|
|
|
(require "lang.rkt") ; for expression?
|
|
|
|
(provide (all-defined-out)) ; too many things to list
|
|
|
|
;;;;;;;;;;;;;;;; expressed values ;;;;;;;;;;;;;;;;
|
|
|
|
;;; an expressed value is either a number, a boolean, a procval, or a
|
|
;;; list of expvals.
|
|
|
|
(define-datatype expval expval?
|
|
(num-val
|
|
(value number?))
|
|
(bool-val
|
|
(boolean boolean?))
|
|
(proc-val
|
|
(proc proc?))
|
|
(list-val
|
|
(lst (list-of expval?))))
|
|
|
|
;;; extractors:
|
|
|
|
(define expval->num
|
|
(lambda (v)
|
|
(cases expval v
|
|
(num-val (num) num)
|
|
(else (expval-extractor-error 'num v)))))
|
|
|
|
(define expval->bool
|
|
(lambda (v)
|
|
(cases expval v
|
|
(bool-val (bool) bool)
|
|
(else (expval-extractor-error 'bool v)))))
|
|
|
|
(define expval->proc
|
|
(lambda (v)
|
|
(cases expval v
|
|
(proc-val (proc) proc)
|
|
(else (expval-extractor-error 'proc v)))))
|
|
|
|
(define expval->list
|
|
(lambda (v)
|
|
(cases expval v
|
|
(list-val (lst) lst)
|
|
(else (expval-extractor-error 'list v)))))
|
|
|
|
(define expval-extractor-error
|
|
(lambda (variant value)
|
|
(eopl:error 'expval-extractors "Looking for a ~s, found ~s"
|
|
variant value)))
|
|
|
|
;; ;;;;;;;;;;;;;;;; continuations ;;;;;;;;;;;;;;;;
|
|
|
|
;; moved to interp.scm
|
|
|
|
;;;;;;;;;;;;;;;; procedures ;;;;;;;;;;;;;;;;
|
|
|
|
(define-datatype proc proc?
|
|
(procedure
|
|
(bvar symbol?)
|
|
(body expression?)
|
|
(env environment?)))
|
|
|
|
;;;;;;;;;;;;;;;; environment structures ;;;;;;;;;;;;;;;;
|
|
|
|
;;; replaced by custom environment structure in environments.scm.
|
|
;;; This represents an environment as an alist ((id rhs) ...)
|
|
;;; where rhs is either an expval or a list (bvar body)
|
|
;;; expval is for extend-env; the list is for extend-env-rec.
|
|
|
|
;;; this representation is designed to make the printed representation
|
|
;;; of the environment more readable.
|
|
|
|
;;; The code for this is in environments.scm, but we need environment?
|
|
;;; for define-datatype proc, so we write an appoximation:
|
|
|
|
(define environment?
|
|
(list-of
|
|
(lambda (p)
|
|
(and
|
|
(pair? p)
|
|
(symbol? (car p))))))
|