385 lines
14 KiB
Scheme
385 lines
14 KiB
Scheme
;; -*-scheme-*-
|
|
;;(define else #t)
|
|
(define (syntax-error message thing)
|
|
(display "syntax-error:")
|
|
(display message)
|
|
(display ":")
|
|
;;(display thing)
|
|
(newline))
|
|
|
|
(display "mes:define-syntax...")
|
|
|
|
;;(define (caddr x) (car (cdr (cdr x))))
|
|
;; (define (caddr x)
|
|
;; (display "wanna caddr:")
|
|
;; (display x)
|
|
;; (newline))
|
|
|
|
;; (define-macro mes:define-syntax
|
|
;; (lambda (form expander)
|
|
;; (expander `(define-macro ,(cadr form)
|
|
;; (let ((transformer ,(caddr form)))
|
|
;; (lambda (form expander)
|
|
;; (expander (transformer form
|
|
;; (lambda (x) x)
|
|
;; eq?)
|
|
;; expander))))
|
|
;; expander)))
|
|
|
|
;; (define (dinges form expander)
|
|
;; (display "dinges form:")
|
|
;; (display form)
|
|
;; (newline)
|
|
;; `(define-macro BOO ;;;,(cadr form)
|
|
;; (let ((transformer ,(caddr form)))
|
|
;; (lambda (form expander)
|
|
;; (expander (transformer form
|
|
;; (lambda (x) x)
|
|
;; eq?)
|
|
;; expander)))))
|
|
|
|
;; (define-macro (mes:define-syntax form expander)
|
|
;; `(expander (dinges form expander)
|
|
;; expander))
|
|
|
|
(define-macro (mes:define-syntax macro-name transformer . stuff)
|
|
;; (display "mes:define-syntax:")
|
|
;; (newline)
|
|
;; (display `(define-macro (,macro-name . args)
|
|
;; (,transformer (cons ',macro-name args)
|
|
;; (lambda (x) x)
|
|
;; eq?)))
|
|
;; (newline)
|
|
`(define-macro (,macro-name . args)
|
|
(,transformer (cons ',macro-name args)
|
|
(lambda (x) x)
|
|
eq?)
|
|
))
|
|
|
|
;; (define-macro (mes:define-syntax form expander)
|
|
;; (expander `(define-macro ,(cadr form)
|
|
;; (let ((transformer ,(caddr form)))
|
|
;; (lambda (form expander)
|
|
;; (expander (transformer form
|
|
;; (lambda (x) x)
|
|
;; eq?)
|
|
;; expander))))
|
|
;; expander))
|
|
|
|
;; (define-macro (mes:define-syntax form expander)
|
|
;; (expander `(define-macro ((cadr form) form expander)
|
|
;; (let ((transformer (caddr form)))
|
|
;; (expander (transformer form
|
|
;; (lambda (x) x)
|
|
;; eq?)
|
|
;; expander)))
|
|
;; expander))
|
|
|
|
(newline)
|
|
|
|
|
|
(display "mes:define-syntax syntax-rules...")
|
|
(newline)
|
|
|
|
(mes:define-syntax syntax-rules
|
|
(let ()
|
|
;; syntax-rules uses defines that get closured-in
|
|
;; mes still has a bug here; move down
|
|
;; (define name? symbol?)
|
|
|
|
;; (define (segment-pattern? pattern)
|
|
;; (and (segment-template? pattern)
|
|
;; (or (null? (cddr pattern))
|
|
;; (syntax-error "segment matching not implemented" pattern))))
|
|
|
|
;; (define (segment-template? pattern)
|
|
;; (and (pair? pattern)
|
|
;; (pair? (cdr pattern))
|
|
;; (memq (cadr pattern) indicators-for-zero-or-more)))
|
|
|
|
;;(define indicators-for-zero-or-more (list (string->symbol "...") '---))
|
|
|
|
(display "BOOO")
|
|
|
|
(lambda (exp r c)
|
|
|
|
;; FIXME: mes, moved down
|
|
(define name? symbol?)
|
|
|
|
(define (segment-pattern? pattern)
|
|
(display "segment-pattern?: ")
|
|
(display pattern)
|
|
(newline)
|
|
(display "segment-template?: ")
|
|
(display (segment-template? pattern))
|
|
(newline)
|
|
(and (segment-template? pattern)
|
|
(or (null? (cddr pattern))
|
|
(syntax-error "segment matching not implemented" pattern))))
|
|
|
|
(define indicators-for-zero-or-more (list (string->symbol "...") '---))
|
|
|
|
(define (segment-template? pattern)
|
|
(and (pair? pattern)
|
|
(display "pair?: ")
|
|
(display (pair? pattern))
|
|
(newline)
|
|
(pair? (cdr pattern))
|
|
(display "pair? cdr: ")
|
|
(display (pair? (cdr pattern)))
|
|
(newline)
|
|
;; (display "indicators: ")
|
|
;; (display indicators-for-zero-or-more)
|
|
;; (newline)
|
|
(display "cadr pattern: ")
|
|
(display (cadr pattern))
|
|
(newline)
|
|
(display "memq?: ")
|
|
;;(memq (cadr pattern) indicators-for-zero-or-more)
|
|
(memq (cadr pattern) (list (string->symbol "...") '---))
|
|
;;(member (cadr pattern) indicators-for-zero-or-more)
|
|
))
|
|
|
|
;; end FIXME
|
|
|
|
|
|
(define %input (r '%input)) ;Gensym these, if you like.
|
|
(define %compare (r '%compare))
|
|
(define %rename (r '%rename))
|
|
(define %tail (r '%tail))
|
|
(define %temp (r '%temp))
|
|
|
|
(define rules (cddr exp))
|
|
(define subkeywords (cadr exp))
|
|
|
|
(define (make-transformer rules)
|
|
(display "make-transformer") (newline)
|
|
`(lambda (,%input ,%rename ,%compare)
|
|
(let ((,%tail (cdr ,%input)))
|
|
(display "TEEL:") (display ,%tail) (newline)
|
|
(cond ,@(map process-rule rules)
|
|
(#t ;;else
|
|
(syntax-error
|
|
"use of macro doesn't match definition"
|
|
,%input))))))
|
|
|
|
(define (process-rule rule)
|
|
(display "process-rule") (newline)
|
|
(cond ((and (pair? rule)
|
|
(pair? (cdr rule))
|
|
(null? (cddr rule)))
|
|
(let ((pattern (cdar rule))
|
|
(template (cadr rule)))
|
|
(let ((xx `,(process-pattern pattern
|
|
%tail
|
|
(lambda (x) x)))
|
|
(tt `,%tail)
|
|
(yy (process-match %tail pattern)))
|
|
(display "METS>>>") (newline)
|
|
(display yy)
|
|
(newline)
|
|
(display "TEEL>>>") (newline)
|
|
(display tt)
|
|
(newline)
|
|
(display "<<<METS") (newline)
|
|
(display "PETTERN>>>") (newline)
|
|
(display xx)
|
|
(newline)
|
|
(display "<<<PETTERN") (newline)
|
|
)
|
|
|
|
`((and ,@(process-match %tail pattern))
|
|
(let* ,(process-pattern pattern
|
|
%tail
|
|
(lambda (x) x))
|
|
,(process-template template
|
|
0
|
|
(meta-variables pattern 0 '()))))))
|
|
(syntax-error "ill-formed syntax rule" rule)))
|
|
|
|
;; Generate code to test whether input expression matches pattern
|
|
|
|
(define (process-match input pattern)
|
|
(display "process-match") (newline)
|
|
(cond ((name? pattern)
|
|
(cond ((member pattern subkeywords)
|
|
`((,%compare ,input (,%rename ',pattern))))
|
|
(#t `())))
|
|
((segment-pattern? pattern)
|
|
(process-segment-match input (car pattern)))
|
|
((pair? pattern)
|
|
`((let ((,%temp ,input))
|
|
(and (pair? ,%temp)
|
|
,@(process-match `(car ,%temp) (car pattern))
|
|
,@(process-match `(cdr ,%temp) (cdr pattern))))))
|
|
((or (null? pattern) (boolean? pattern) (char? pattern))
|
|
`((eq? ,input ',pattern)))
|
|
(#t ;;else
|
|
`((equal? ,input ',pattern)))))
|
|
|
|
(define (process-segment-match input pattern)
|
|
(display "process-segment-match") (newline)
|
|
(let ((conjuncts (process-match '(car l) pattern)))
|
|
(cond ((null? conjuncts)
|
|
`((list? ,input))) ;+++
|
|
(#t `((let loop ((l ,input))
|
|
(display "loop") (newline)
|
|
(or (null? l)
|
|
(and (pair? l)
|
|
,@conjuncts
|
|
(loop (cdr l))))))))))
|
|
|
|
;; Generate code to take apart the input expression
|
|
;; This is pretty bad, but it seems to work (can't say why).
|
|
|
|
(define (process-pattern pattern path mapit)
|
|
(display "process-pattern pattern=") (display pattern) (newline)
|
|
(cond ((name? pattern)
|
|
(display "name!") (newline)
|
|
(display "subkeywords: ") (display subkeywords) (newline)
|
|
(cond ((memq pattern subkeywords)
|
|
;;;;(member pattern subkeywords)
|
|
'())
|
|
(#t
|
|
(display "hiero mapit=") (display mapit)
|
|
(display " path=") (display path)
|
|
(newline)
|
|
(list (list pattern (mapit path))))))
|
|
((segment-pattern? pattern)
|
|
(display "segment!") (newline)
|
|
(process-pattern (car pattern)
|
|
%temp
|
|
(lambda (x) ;temp is free in x
|
|
(display "mapit x=") (display x) (newline)
|
|
(mapit (cond ((eq? %temp x)
|
|
;; guile: x=%temp ==> mapit==> (cdr %tail)
|
|
;; mes: x=%temp ==> mapit==> %temp
|
|
(display " x=%temp ==> mapit==> ") (display path) (newline)
|
|
path) ;+++
|
|
(#t
|
|
(display "not!")
|
|
`(map (lambda (,%temp) ,x)
|
|
,path)))))))
|
|
((pair? pattern)
|
|
(display "pair!") (newline)
|
|
(append (process-pattern (car pattern) `(car ,path) mapit)
|
|
(process-pattern (cdr pattern) `(cdr ,path) mapit)))
|
|
(#t ;;else
|
|
(display "else!") (newline)
|
|
'())))
|
|
|
|
;; Generate code to compose the output expression according to template
|
|
|
|
(define (process-template template rank env)
|
|
(display "process-template") (newline)
|
|
(cond ((name? template)
|
|
(let ((probe (assq template env)))
|
|
(cond (probe
|
|
(cond ((<= (cdr probe) rank)
|
|
template)
|
|
(#t (syntax-error "template rank error (too few ...'s?)"
|
|
template))))
|
|
(#t `(,%rename ',template)))))
|
|
((segment-template? template)
|
|
(let ((vars
|
|
(free-meta-variables (car template) (+ rank 1) env '())))
|
|
(cond ((null? vars)
|
|
(syntax-error "too many ...'s" template))
|
|
(#t (let* ((x (process-template (car template)
|
|
(+ rank 1)
|
|
env))
|
|
(gen (cond ((equal? (list x) vars)
|
|
x) ;+++
|
|
(#t `(map (lambda ,vars ,x)
|
|
,@vars)))))
|
|
(cond ((null? (cddr template))
|
|
gen) ;+++
|
|
(#t `(append ,gen ,(process-template (cddr template)
|
|
rank env)))))))))
|
|
((pair? template)
|
|
`(cons ,(process-template (car template) rank env)
|
|
,(process-template (cdr template) rank env)))
|
|
(#t ;;else
|
|
`(quote ,template))))
|
|
|
|
;; Return an association list of (var . rank)
|
|
|
|
(define (meta-variables pattern rank vars)
|
|
(display "meta-variables") (newline)
|
|
(cond ((name? pattern)
|
|
(cond ((memq pattern subkeywords)
|
|
vars)
|
|
(#t (cons (cons pattern rank) vars))))
|
|
((segment-pattern? pattern)
|
|
(meta-variables (car pattern) (+ rank 1) vars))
|
|
((pair? pattern)
|
|
(meta-variables (car pattern) rank
|
|
(meta-variables (cdr pattern) rank vars)))
|
|
(#t ;;else
|
|
vars)))
|
|
|
|
;; Return a list of meta-variables of given higher rank
|
|
|
|
(define (free-meta-variables template rank env free)
|
|
(display "free-meta-variables") (newline)
|
|
(cond ((name? template)
|
|
(cond ((and (not (memq template free))
|
|
(let ((probe (assq template env)))
|
|
(and probe (>= (cdr probe) rank))))
|
|
(cons template free))
|
|
(#t free)))
|
|
((segment-template? template)
|
|
(free-meta-variables (car template)
|
|
rank env
|
|
(free-meta-variables (cddr template)
|
|
rank env free)))
|
|
((pair? template)
|
|
(free-meta-variables (car template)
|
|
rank env
|
|
(free-meta-variables (cdr template)
|
|
rank env free)))
|
|
(#t ;;else
|
|
free)))
|
|
|
|
c ;ignored
|
|
|
|
(display "HELLO")
|
|
(newline)
|
|
|
|
;; Kludge for Scheme48 linker.
|
|
;; `(cons ,(make-transformer rules)
|
|
;; ',(find-free-names-in-syntax-rules subkeywords rules))
|
|
|
|
(make-transformer rules))))
|
|
|
|
|
|
(mes:define-syntax mes:or
|
|
(syntax-rules ()
|
|
((mes:or) #f)
|
|
((mes:or e) e)
|
|
((mes:or e1 e ...) (let ((temp e1))
|
|
(cond (temp temp) (#t (or e ...)))))))
|
|
|
|
(display "(mes:or #f (= 0 1) 'hello-syntax-world): ")
|
|
(display (mes:or #f (= 0 1) 'hello-syntax-world))
|
|
(display (mes:or #f '==>baaa))
|
|
(newline)
|
|
|
|
(mes:define-syntax mes:when
|
|
(syntax-rules ()
|
|
((when condition exp ...)
|
|
(if condition
|
|
(begin exp ...)))))
|
|
|
|
(display (mes:when #t "when:hello syntax world"))
|
|
|
|
;; (define-macro (when cond exp . rest)
|
|
;; `(if ,cond
|
|
;; (begin ,exp . ,rest)))
|
|
|
|
|
|
;; (define-macro (when clause . rest)
|
|
;; (list 'cond (list clause (list 'let '() rest))))
|
|
(newline)
|
|
'syntax-dun
|