Scheme meta-circular evaluator
About
A Scheme meta-circular evaluator from SICP chapter 4.
Quickstart
Environment
I use MIT/GNU-Scheme 9.2 on OS X 10.11.
Interactive mode
The default interface is an interactive loop, try this:
$ scheme
1 ]=> (load "main.scm")
(load "main.scm")
;Loading "main.scm"...
; Loading "environment.scm"...
; Loading "primitives.scm"... done
; ... done
; Loading "io.scm"... done
; Loading "procedure.scm"... done
; Loading "utils.scm"... done
;; Meta-circular-evaluater input:
Then have fun testing whatever you want. Note that do not load "main.scm" twice, or nested apply would cause problems.
Input from file
Load "main.scm" in scheme shell, then load file like this:
;; Meta-circular-evaluater input:
(load "input.scm")
Features
- Support lexical binding.
- Support let*/letrec/named-let
;; Meta-circular-evaluater input:
(define (f x) (letrec ((even? (lambda (n) (if (= n 0) #t (odd? (- n 1))))) (odd? (lambda (n) (if (= n 0) #f (even? (- n 1)))))) (even? x)))
;; Result:
ok
;; Meta-circular-evaluater input:
(f 5)
;; Result:
#f
;; Meta-circular-evaluater input:
(f 1022)
;; Result:
#t
TODO
- let*
- letrec
- Named let
- Input from file
- Separate syntatic anslysis from execution (SICP 4.1.7)
- Lazy evatuating (SICP 4.2)