mes/module/mes/mes-0.mes
Jan Nieuwenhuizen 661954a352 Update Mes in Guile.
* guile/mes.scm: Update for guile-2.2.
* guile/mes.mes: Update from module/mes/mes-0.mes.
* guile/reader.mes: Update from module/mes/read-0.mes.
2016-12-12 20:35:19 +01:00

185 lines
6.2 KiB
Scheme

;;; -*-scheme-*-
;;; Mes --- Maxwell Equations of Software
;;; Copyright © 2016 Jan Nieuwenhuizen <janneke@gnu.org>
;;;
;;; This file is part of Mes.
;;;
;;; Mes is free software; you can redistribute it and/or modify it
;;; under the terms of the GNU General Public License as published by
;;; the Free Software Foundation; either version 3 of the License, or (at
;;; your option) any later version.
;;;
;;; Mes is distributed in the hope that it will be useful, but
;;; WITHOUT ANY WARRANTY; without even the implied warranty of
;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
;;; GNU General Public License for more details.
;;;
;;; You should have received a copy of the GNU General Public License
;;; along with Mes. If not, see <http://www.gnu.org/licenses/>.
;;; Commentary:
;;; mes-0.mes - bootstrap into Scheme, re
;;; When compiling mes.c with -DBOOT=1, eval/apply et al. are lacking
;;; features wrt the fat-c variant, e.g., define and define-macro are
;;; not available; instead label is supplied. Before loading
;;; boot-0.mes, loop-0.mes is loaded to provide a richer eval/apply.
;;; This might enable moving more functionality from C to Scheme,
;;; making the entirely-from-source bootstrap process more feasible.
;;; However, currently performance is 400x worse. Also several tests
;;; in the test suite fail and the REPL does not work yet.
;;; Code:
(define-macro (cond . clauses)
(list 'if (null? clauses) *unspecified*
(if (null? (cdr clauses))
(list 'if (car (car clauses))
(list (cons 'lambda (cons '() (cons (car (car clauses)) (cdr (car clauses))))))
*unspecified*)
(if (eq? (car (cadr clauses)) 'else)
(list 'if (car (car clauses))
(list (cons 'lambda (cons '() (car clauses))))
(list (cons 'lambda (cons '() (cons *unspecified* (cdr (cadr clauses)))))))
(list 'if (car (car clauses))
(list (cons 'lambda (cons '() (car clauses))))
(cons 'cond (cdr clauses)))))))
(define (map f l . r)
(if (null? l) '()
(if (null? r) (cons (f (car l)) (map f (cdr l)))
(if (null? (cdr r))
(cons (f (car l) (caar r)) (map f (cdr l) (cdar r)))))))
(define-macro (simple-let bindings . rest)
(cons (cons 'lambda (cons (map car bindings) rest))
(map cadr bindings)))
(define-macro (let bindings . rest)
(cons 'simple-let (cons bindings rest)))
(define-macro (or . x)
(if (null? x) #f
(if (null? (cdr x)) (car x)
(list 'if (car x) (car x)
(cons 'or (cdr x))))))
(define-macro (and . x)
(if (null? x) #t
(if (null? (cdr x)) (car x)
(list 'if (car x) (cons 'and (cdr x))
#f))))
(define (not x)
(if x #f #t))
(define (evlis-env m a)
(cond
((null? m) '())
((not (pair? m)) (eval-env m a))
(#t (cons (eval-env (car m) a) (evlis-env (cdr m) a)))))
(define (apply-env fn x a)
(cond
((atom? fn)
(cond
((builtin? fn) (call fn x))
((eq? fn 'call-with-values) (call call-with-values-env (append x (cons a '()))))
((eq? fn 'current-module) a)
(#t (apply-env (eval-env fn a) x a))))
((eq? (car fn) 'lambda)
(let ((p (pairlis (cadr fn) x a)))
(eval-begin-env (cddr fn) (cons (cons '*closure* p) p))))
((eq? (car fn) '*closure*)
(let ((args (caddr fn))
(body (cdddr fn))
(a (cddr (cadr fn))))
(let ((p (pairlis args x a)))
(eval-begin-env body (cons (cons '*closure* p) p)))))
;;((eq? (car fn) 'label) (apply-env (caddr fn) x (cons (cons (cadr fn) (caddr fn)) a)))
(#t (apply-env (eval-env fn a) x a))))
(define (eval-expand e a)
(cond
((symbol? e) (assq-ref-cache e a))
((atom? e) e)
((atom? (car e))
(cond
((eq? (car e) 'quote) (cadr e))
((eq? (car e) 'syntax) (cadr e))
((eq? (car e) 'begin) (eval-begin-env e a))
((eq? (car e) 'lambda) (make-closure (cadr e) (cddr e) (assq '*closure* a)))
((eq? (car e) '*closure*) e)
((eq? (car e) 'if) (eval-if-env (cdr e) a))
((eq? (car e) 'define) (env:define (cons (sexp:define e a) '()) a))
((eq? (car e) 'define-macro) (env:define (env:macro (sexp:define e a)) a))
((eq? (car e) 'set!) (set-env! (cadr e) (eval-env (caddr e) a) a))
((eq? (car e) 'apply-env) (apply-env (eval-env (cadr e) a) (evlis-env (caddr e) a) a))
((eq? (car e) 'unquote) (eval-env (cadr e) a))
((eq? (car e) 'quasiquote) (eval-quasiquote (cadr e) (add-unquoters a)))
(#t (apply-env (car e) (evlis-env (cdr e) a) a))))
(#t (apply-env (car e) (evlis-env (cdr e) a) a))))
(define (unquote x) (cons 'unquote x))
(define (unquote-splicing x) (cons 'quasiquote x))
(define %the-unquoters
(cons
(cons 'unquote unquote)
(cons (cons 'unquote-splicing unquote-splicing) '())))
(define (add-unquoters a)
(cons %the-unquoters a))
(define (eval-env e a)
(eval-expand (expand-macro-env e a) a))
(define (expand-macro-env e a)
(if (pair? e) ((lambda (macro)
(if macro (expand-macro-env (apply-env macro (cdr e) a) a)
e))
(lookup-macro (car e) a))
e))
(define (eval-begin-env e a)
(if (null? e) *unspecified*
(if (null? (cdr e)) (eval-env (car e) a)
(begin
(eval-env (car e) a)
(eval-begin-env (cdr e) a)))))
(define (eval-if-env e a)
(if (eval-env (car e) a) (eval-env (cadr e) a)
(if (pair? (cddr e)) (eval-env (caddr e) a))))
(define (eval-quasiquote e a)
(cond ((null? e) e)
((atom? e) e)
((eq? (car e) 'unquote) (eval-env (cadr e) a))
((and (pair? (car e))
(eq? (caar e) 'unquote-splicing))
(append2 (eval-env (cadar e) a) (eval-quasiquote (cdr e) a)))
(#t (cons (eval-quasiquote (car e) a) (eval-quasiquote (cdr e) a)))))
(define (sexp:define e a)
(if (atom? (cadr e)) (cons (cadr e) (eval-env (caddr e) a))
(cons (caadr e) (eval-env (cons 'lambda (cons (cdadr e) (cddr e))) a))))
(define (env:define a+ a)
(set-cdr! a+ (cdr a))
(set-cdr! a a+)
(set-cdr! (assq '*closure* a) a))
(define (env:macro name+entry)
(cons
(cons (car name+entry)
(make-macro (car name+entry)
(cdr name+entry)))
'()))
;; boot into loop-0
()