implement parameterize

This commit is contained in:
Yuichi Nishiwaki 2014-09-15 15:44:57 +09:00
parent 788ac686af
commit 0a0c085003
1 changed files with 58 additions and 0 deletions

58
boot.c
View File

@ -300,6 +300,34 @@ my $src = <<'EOL';
`(,(r 'begin) ,@(cdr clause)))
,(loop (cdr clauses)))))))))))
(define (dynamic-bind parameters values body)
(let* ((old-bindings
(current-dynamic-environment))
(binding
(let ((dict (dictionary)))
(for-each
(lambda (parameter value)
(dictionary-set! dict parameter (list (parameter value #f))))
parameters
values)
dict))
(new-bindings
(cons binding old-bindings)))
(dynamic-wind
(lambda () (current-dynamic-environment new-bindings))
body
(lambda () (current-dynamic-environment old-bindings)))))
(define-syntax parameterize
(er-macro-transformer
(lambda (form r compare)
(let ((formal (cadr form))
(body (cddr form)))
`(,(r 'dynamic-bind)
(list ,@(map car formal))
(list ,@(map cadr formal))
(,(r 'lambda) () ,@body))))))
(define-syntax letrec-syntax
(er-macro-transformer
(lambda (form r c)
@ -322,6 +350,7 @@ my $src = <<'EOL';
and or
cond case else =>
do when unless
parameterize
let-syntax letrec-syntax
syntax-error))
@ -668,6 +697,34 @@ const char pic_boot[] =
" `(,(r 'begin) ,@(cdr clause)))\n"
" ,(loop (cdr clauses)))))))))))\n"
"\n"
" (define (dynamic-bind parameters values body)\n"
" (let* ((old-bindings\n"
" (current-dynamic-environment))\n"
" (binding\n"
" (let ((dict (dictionary)))\n"
" (for-each\n"
" (lambda (parameter value)\n"
" (dictionary-set! dict parameter (list (parameter value #f))))\n"
" parameters\n"
" values)\n"
" dict))\n"
" (new-bindings\n"
" (cons binding old-bindings)))\n"
" (dynamic-wind\n"
" (lambda () (current-dynamic-environment new-bindings))\n"
" body\n"
" (lambda () (current-dynamic-environment old-bindings)))))\n"
"\n"
" (define-syntax parameterize\n"
" (er-macro-transformer\n"
" (lambda (form r compare)\n"
" (let ((formal (cadr form))\n"
" (body (cddr form)))\n"
" `(,(r 'dynamic-bind)\n"
" (list ,@(map car formal))\n"
" (list ,@(map cadr formal))\n"
" (,(r 'lambda) () ,@body))))))\n"
"\n"
" (define-syntax letrec-syntax\n"
" (er-macro-transformer\n"
" (lambda (form r c)\n"
@ -690,6 +747,7 @@ const char pic_boot[] =
" and or\n"
" cond case else =>\n"
" do when unless\n"
" parameterize\n"
" let-syntax letrec-syntax\n"
" syntax-error))\n"
;