clean up code
This commit is contained in:
Yuito Murase
parent
85db821ad2
commit
7af2f1e11d
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@ -1,335 +1,321 @@
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(import (scheme base)
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(scheme cxr)
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(picrin macro)
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(scheme write))
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(define-library (picrin syntax-rules)
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(import (scheme base)
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(scheme cxr)
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(picrin macro))
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;;; utility functions
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(define (reverse* l)
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;; (reverse* '(a b c d . e)) => (e d c b a)
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(let loop ((a '())
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(d l))
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(if (pair? d)
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(loop (cons (car d) a) (cdr d))
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(cons d a))))
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(define (reverse* l)
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;; (reverse* '(a b c d . e)) => (e d c b a)
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(let loop ((a '())
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(d l))
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(if (pair? d)
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(loop (cons (car d) a) (cdr d))
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(cons d a))))
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(define (var->sym v)
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(let loop ((cnt 0)
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(v v))
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(if (symbol? v)
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(string->symbol (string-append (symbol->string v) "/" (number->string cnt)))
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(loop (+ 1 cnt) (car v)))))
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(define (var->sym v)
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(let loop ((cnt 0)
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(v v))
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(if (symbol? v)
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(string->symbol (string-append (symbol->string v) "/" (number->string cnt)))
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(loop (+ 1 cnt) (car v)))))
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(define push-var list)
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(define push-var list)
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(define (every? pred l)
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(if (null? l)
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#t
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(and (pred (car l)) (every? pred (cdr l)))))
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(define (every? pred l)
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(if (null? l)
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#t
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(and (pred (car l)) (every? pred (cdr l)))))
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(define (flatten l)
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(cond
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((null? l) '())
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((pair? (car l))
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(append (flatten (car l)) (flatten (cdr l))))
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(else
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(cons (car l) (flatten (cdr l))))))
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(define (flatten l)
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(cond
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((null? l) '())
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((pair? (car l))
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(append (flatten (car l)) (flatten (cdr l))))
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(else
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(cons (car l) (flatten (cdr l))))))
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;;; main function
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(define-syntax syntax-rules
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(er-macro-transformer
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(lambda (form r compare)
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(define _define (r 'define))
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(define _let (r 'let))
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(define _if (r 'if))
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(define _begin (r 'begin))
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(define _lambda (r 'lambda))
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(define _set! (r 'set!))
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(define _not (r 'not))
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(define _and (r 'and))
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(define _car (r 'car))
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(define _cdr (r 'cdr))
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(define _cons (r 'cons))
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(define _pair? (r 'pair?))
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(define _null? (r 'null?))
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(define _symbol? (r 'symbol?))
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(define _eqv? (r 'eqv?))
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(define _string=? (r 'string=?))
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(define _map (r 'map))
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(define _vector->list (r 'vector->list))
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(define _list->vector (r 'list->vector))
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(define _quote (r 'quote))
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(define _quasiquote (r 'quasiquote))
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(define _unquote (r 'unquote))
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(define _unquote-splicing (r 'unquote-splicing))
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(define _syntax-error (r 'syntax-error))
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(define _call/cc (r 'call/cc))
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(define _er-macro-transformer (r 'er-macro-transformer))
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;;; main function
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(define-syntax syntax-rules
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(er-macro-transformer
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(lambda (form r compare)
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(define _define (r 'define))
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(define _let (r 'let))
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(define _if (r 'if))
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(define _begin (r 'begin))
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(define _lambda (r 'lambda))
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(define _set! (r 'set!))
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(define _not (r 'not))
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(define _and (r 'and))
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(define _car (r 'car))
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(define _cdr (r 'cdr))
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(define _cons (r 'cons))
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(define _pair? (r 'pair?))
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(define _null? (r 'null?))
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(define _symbol? (r 'symbol?))
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(define _eqv? (r 'eqv?))
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(define _string=? (r 'string=?))
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(define _map (r 'map))
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(define _vector->list (r 'vector->list))
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(define _list->vector (r 'list->vector))
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(define _quote (r 'quote))
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(define _quasiquote (r 'quasiquote))
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(define _unquote (r 'unquote))
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(define _unquote-splicing (r 'unquote-splicing))
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(define _syntax-error (r 'syntax-error))
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(define _call/cc (r 'call/cc))
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(define _er-macro-transformer (r 'er-macro-transformer))
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(define (compile-match ellipsis literals pattern)
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(letrec ((compile-match-base
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(lambda (pattern)
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(cond ((compare pattern (r '_)) (values #f '()))
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((member pattern literals compare)
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(values
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`(,_if (,_and (,_symbol? expr) (cmp expr (rename ',pattern)))
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#f
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(exit #f))
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'()))
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((and ellipsis (compare pattern ellipsis))
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(values `(,_syntax-error "invalid pattern") '()))
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((symbol? pattern)
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(values `(,_set! ,(var->sym pattern) expr) (list pattern)))
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((pair? pattern)
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(compile-match-list pattern))
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((vector? pattern)
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(compile-match-vector pattern))
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((string? pattern)
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(values
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`(,_if (,_not (,_string=? ',pattern expr))
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(exit #f))
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'()))
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(else
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(values
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`(,_if (,_not (,_eqv? ',pattern expr))
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(exit #f))
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'())))))
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(compile-match-list
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(lambda (pattern)
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(let loop ((pattern pattern)
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(matches '())
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(vars '())
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(accessor 'expr))
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(cond ;; (hoge)
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((not (pair? (cdr pattern)))
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(let*-values (((match1 vars1) (compile-match-base (car pattern)))
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((match2 vars2) (compile-match-base (cdr pattern))))
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(values
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`(,_begin ,@(reverse matches)
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(,_if (,_pair? ,accessor)
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(,_begin
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(,_let ((expr (,_car ,accessor)))
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,match1)
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(,_let ((expr (,_cdr ,accessor)))
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,match2))
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(exit #f)))
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(append vars (append vars1 vars2)))))
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;; (hoge ... rest args)
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((and ellipsis (compare (cadr pattern) ellipsis))
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(let-values (((match-r vars-r) (compile-match-list-reverse pattern)))
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(values
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`(,_begin ,@(reverse matches)
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(,_let ((expr (,_let loop ((a ())
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(d ,accessor))
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(,_if (,_pair? d)
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(loop (,_cons (,_car d) a) (,_cdr d))
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(,_cons d a)))))
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,match-r))
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(append vars vars-r))))
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(else
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(let-values (((match1 vars1) (compile-match-base (car pattern))))
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(loop (cdr pattern)
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(cons `(,_if (,_pair? ,accessor)
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(,_let ((expr (,_car,accessor)))
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,match1)
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(exit #f))
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matches)
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(append vars vars1)
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`(,_cdr ,accessor))))))))
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(compile-match-list-reverse
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(lambda (pattern)
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(let loop ((pattern (reverse* pattern))
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(matches '())
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(vars '())
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(accessor 'expr))
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(cond ((and ellipsis (compare (car pattern) ellipsis))
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(let-values (((match1 vars1) (compile-match-ellipsis (cadr pattern))))
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(values
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`(,_begin ,@(reverse matches)
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(,_let ((expr ,accessor))
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,match1))
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(append vars vars1))))
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(define (compile-match ellipsis literals pattern)
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(letrec ((compile-match-base
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(lambda (pattern)
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(cond ((compare pattern (r '_)) (values #f '()))
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((member pattern literals compare)
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(values
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`(,_if (,_and (,_symbol? expr) (cmp expr (rename ',pattern)))
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#f
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(exit #f))
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'()))
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((and ellipsis (compare pattern ellipsis))
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(values `(,_syntax-error "invalid pattern") '()))
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((symbol? pattern)
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(values `(,_set! ,(var->sym pattern) expr) (list pattern)))
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((pair? pattern)
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(compile-match-list pattern))
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((vector? pattern)
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(compile-match-vector pattern))
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((string? pattern)
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(values
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`(,_if (,_not (,_string=? ',pattern expr))
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(exit #f))
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'()))
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(else
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(let-values (((match1 vars1) (compile-match-base (car pattern))))
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(loop (cdr pattern)
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(cons `(,_let ((expr (,_car ,accessor))) ,match1) matches)
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(append vars vars1)
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`(,_cdr ,accessor))))))))
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(values
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`(,_if (,_not (,_eqv? ',pattern expr))
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(exit #f))
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'())))))
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(compile-match-ellipsis
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(lambda (pattern)
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(let-values (((match vars) (compile-match-base pattern)))
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(values
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`(,_let loop ((expr expr))
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(,_if (,_not (,_null? expr))
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(,_let ,(map (lambda (var) `(,(var->sym var) '())) vars)
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(,_let ((expr (,_car expr)))
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,match)
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,@(map
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(lambda (var)
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`(,_set! ,(var->sym (push-var var))
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(,_cons ,(var->sym var) ,(var->sym (push-var var)))))
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vars)
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(loop (,_cdr expr)))))
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(map push-var vars)))))
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(compile-match-list
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(lambda (pattern)
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(let loop ((pattern pattern)
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(matches '())
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(vars '())
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(accessor 'expr))
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(cond ;; (hoge)
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((not (pair? (cdr pattern)))
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(let*-values (((match1 vars1) (compile-match-base (car pattern)))
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((match2 vars2) (compile-match-base (cdr pattern))))
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(values
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`(,_begin ,@(reverse matches)
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(,_if (,_pair? ,accessor)
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(,_begin
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(,_let ((expr (,_car ,accessor)))
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,match1)
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(,_let ((expr (,_cdr ,accessor)))
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,match2))
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(exit #f)))
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(append vars (append vars1 vars2)))))
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;; (hoge ... rest args)
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((and ellipsis (compare (cadr pattern) ellipsis))
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(let-values (((match-r vars-r) (compile-match-list-reverse pattern)))
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(values
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`(,_begin ,@(reverse matches)
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(,_let ((expr (,_let loop ((a ())
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(d ,accessor))
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(,_if (,_pair? d)
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(loop (,_cons (,_car d) a) (,_cdr d))
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(,_cons d a)))))
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,match-r))
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(append vars vars-r))))
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(else
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(let-values (((match1 vars1) (compile-match-base (car pattern))))
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(loop (cdr pattern)
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(cons `(,_if (,_pair? ,accessor)
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(,_let ((expr (,_car,accessor)))
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,match1)
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(exit #f))
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matches)
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(append vars vars1)
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`(,_cdr ,accessor))))))))
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(compile-match-vector
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(lambda (pattern)
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(let-values (((match vars) (compile-match-list (vector->list pattern))))
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(values
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`(,_let ((expr (,_vector->list expr)))
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,match)
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vars)))))
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(compile-match-list-reverse
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(lambda (pattern)
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(let loop ((pattern (reverse* pattern))
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(matches '())
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(vars '())
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(accessor 'expr))
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(cond ((and ellipsis (compare (car pattern) ellipsis))
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(let-values (((match1 vars1) (compile-match-ellipsis (cadr pattern))))
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(values
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`(,_begin ,@(reverse matches)
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(,_let ((expr ,accessor))
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,match1))
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(append vars vars1))))
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(else
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(let-values (((match1 vars1) (compile-match-base (car pattern))))
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(loop (cdr pattern)
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(cons `(,_let ((expr (,_car ,accessor))) ,match1) matches)
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(append vars vars1)
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`(,_cdr ,accessor))))))))
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(let-values (((match vars) (compile-match-base (cdr pattern))))
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(values `(,_let ((expr (,_cdr expr)))
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,match
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#t)
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vars))))
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(compile-match-ellipsis
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(lambda (pattern)
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(let-values (((match vars) (compile-match-base pattern)))
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(values
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`(,_let loop ((expr expr))
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(,_if (,_not (,_null? expr))
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(,_let ,(map (lambda (var) `(,(var->sym var) '())) vars)
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(,_let ((expr (,_car expr)))
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,match)
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,@(map
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(lambda (var)
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`(,_set! ,(var->sym (push-var var))
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(,_cons ,(var->sym var) ,(var->sym (push-var var)))))
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vars)
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(loop (,_cdr expr)))))
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(map push-var vars)))))
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;;; compile expand
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(define (compile-expand ellipsis reserved template)
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(letrec ((compile-expand-base
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(lambda (template ellipsis-valid)
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(cond ((member template reserved compare)
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(values (var->sym template) (list template)))
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((symbol? template)
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(values `(rename ',template) '()))
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((pair? template)
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(compile-expand-list template ellipsis-valid))
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((vector? template)
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(compile-expand-vector template ellipsis-valid))
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(else
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(values `',template '())))))
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(compile-match-vector
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(lambda (pattern)
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(let-values (((match vars) (compile-match-list (vector->list pattern))))
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(values
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`(,_let ((expr (,_vector->list expr)))
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,match)
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vars)))))
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(compile-expand-list
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(lambda (template ellipsis-valid)
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(let loop ((template template)
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(expands '())
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(vars '()))
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(cond ;; (... hoge)
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((and ellipsis-valid
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(pair? template)
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(compare (car template) ellipsis))
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(if (and (pair? (cdr template)) (null? (cddr template)))
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(compile-expand-base (cadr template) #f)
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(values '(,_syntax-error "invalid template") '())))
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;; hoge
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((not (pair? template))
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(let-values (((expand1 vars1)
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(compile-expand-base template ellipsis-valid)))
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(values
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`(,_quasiquote (,@(reverse expands) . (,_unquote ,expand1)))
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(append vars vars1))))
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;; (a ... rest syms)
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((and ellipsis-valid
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(pair? (cdr template))
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(compare (cadr template) ellipsis))
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(let-values (((expand1 vars1)
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(compile-expand-base (car template) ellipsis-valid)))
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(loop (cddr template)
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(cons
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`(,_unquote-splicing
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(,_map (,_lambda ,(map var->sym vars1) ,expand1)
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,@(map (lambda (v) (var->sym (push-var v))) vars1)))
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expands)
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(append vars (map push-var vars1)))))
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(else
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(let-values (((expand1 vars1)
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(compile-expand-base (car template) ellipsis-valid)))
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(loop (cdr template)
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(cons
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`(,_unquote ,expand1)
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expands)
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(append vars vars1))))))))
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(let-values (((match vars) (compile-match-base (cdr pattern))))
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(values `(,_let ((expr (,_cdr expr)))
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,match
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#t)
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vars))))
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(compile-expand-vector
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(lambda (template ellipsis-valid)
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(let-values (((expand1 vars1)
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(compile-expand-list (vector->list template) ellipsis-valid)))
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`(,_list->vector ,expand1)
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vars1))))
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;;; compile expand
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(define (compile-expand ellipsis reserved template)
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(letrec ((compile-expand-base
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(lambda (template ellipsis-valid)
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(cond ((member template reserved compare)
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(values (var->sym template) (list template)))
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((symbol? template)
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(values `(rename ',template) '()))
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((pair? template)
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(compile-expand-list template ellipsis-valid))
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((vector? template)
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(compile-expand-vector template ellipsis-valid))
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(else
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(values `',template '())))))
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|
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(compile-expand-base template ellipsis)))
|
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(compile-expand-list
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(lambda (template ellipsis-valid)
|
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(let loop ((template template)
|
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(expands '())
|
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(vars '()))
|
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(cond ;; (... hoge)
|
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((and ellipsis-valid
|
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(pair? template)
|
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(compare (car template) ellipsis))
|
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(if (and (pair? (cdr template)) (null? (cddr template)))
|
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(compile-expand-base (cadr template) #f)
|
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(values '(,_syntax-error "invalid template") '())))
|
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;; hoge
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((not (pair? template))
|
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(let-values (((expand1 vars1)
|
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(compile-expand-base template ellipsis-valid)))
|
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(values
|
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`(,_quasiquote (,@(reverse expands) . (,_unquote ,expand1)))
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(append vars vars1))))
|
||||
;; (a ... rest syms)
|
||||
((and ellipsis-valid
|
||||
(pair? (cdr template))
|
||||
(compare (cadr template) ellipsis))
|
||||
(let-values (((expand1 vars1)
|
||||
(compile-expand-base (car template) ellipsis-valid)))
|
||||
(loop (cddr template)
|
||||
(cons
|
||||
`(,_unquote-splicing
|
||||
(,_map (,_lambda ,(map var->sym vars1) ,expand1)
|
||||
,@(map (lambda (v) (var->sym (push-var v))) vars1)))
|
||||
expands)
|
||||
(append vars (map push-var vars1)))))
|
||||
(else
|
||||
(let-values (((expand1 vars1)
|
||||
(compile-expand-base (car template) ellipsis-valid)))
|
||||
(loop (cdr template)
|
||||
(cons
|
||||
`(,_unquote ,expand1)
|
||||
expands)
|
||||
(append vars vars1))))))))
|
||||
|
||||
(define (check-vars vars-pattern vars-template)
|
||||
;;fixme
|
||||
#t)
|
||||
(compile-expand-vector
|
||||
(lambda (template ellipsis-valid)
|
||||
(let-values (((expand1 vars1)
|
||||
(compile-expand-list (vector->list template) ellipsis-valid)))
|
||||
`(,_list->vector ,expand1)
|
||||
vars1))))
|
||||
|
||||
(define (compile-rule ellipsis literals rule)
|
||||
(let ((pattern (car rule))
|
||||
(template (cadr rule)))
|
||||
(let*-values (((match vars-match)
|
||||
(compile-match ellipsis literals pattern))
|
||||
((expand vars-expand)
|
||||
(compile-expand ellipsis (flatten vars-match) template)))
|
||||
(if (check-vars vars-match vars-expand)
|
||||
(list vars-match match expand)
|
||||
'mismatch))))
|
||||
(compile-expand-base template ellipsis)))
|
||||
|
||||
(define (expand-clauses clauses rename)
|
||||
(cond ((null? clauses)
|
||||
`(,_quote (syntax-error "no matching pattern")))
|
||||
((compare (car clauses) 'mismatch)
|
||||
`(,_syntax-error "invalid rule"))
|
||||
(else
|
||||
(let ((vars (car (car clauses)))
|
||||
(match (cadr (car clauses)))
|
||||
(expand (caddr (car clauses))))
|
||||
`(,_let ,(map (lambda (v) (list (var->sym v) '())) vars)
|
||||
(,_let ((result (,_call/cc (,_lambda (exit) ,match))))
|
||||
(,_if result
|
||||
,expand
|
||||
,(expand-clauses (cdr clauses) rename))))))))
|
||||
(define (check-vars vars-pattern vars-template)
|
||||
;;fixme
|
||||
#t)
|
||||
|
||||
(define (normalize-form form)
|
||||
(if (and (list? form) (>= (length form) 2))
|
||||
(let ((ellipsis '...)
|
||||
(literals (cadr form))
|
||||
(rules (cddr form)))
|
||||
(define (compile-rule ellipsis literals rule)
|
||||
(let ((pattern (car rule))
|
||||
(template (cadr rule)))
|
||||
(let*-values (((match vars-match)
|
||||
(compile-match ellipsis literals pattern))
|
||||
((expand vars-expand)
|
||||
(compile-expand ellipsis (flatten vars-match) template)))
|
||||
(if (check-vars vars-match vars-expand)
|
||||
(list vars-match match expand)
|
||||
'mismatch))))
|
||||
|
||||
(when (symbol? literals)
|
||||
(set! ellipsis literals)
|
||||
(set! literals (car rules))
|
||||
(set! rules (cdr rules)))
|
||||
(define (expand-clauses clauses rename)
|
||||
(cond ((null? clauses)
|
||||
`(,_quote (syntax-error "no matching pattern")))
|
||||
((compare (car clauses) 'mismatch)
|
||||
`(,_syntax-error "invalid rule"))
|
||||
(else
|
||||
(let ((vars (car (car clauses)))
|
||||
(match (cadr (car clauses)))
|
||||
(expand (caddr (car clauses))))
|
||||
`(,_let ,(map (lambda (v) (list (var->sym v) '())) vars)
|
||||
(,_let ((result (,_call/cc (,_lambda (exit) ,match))))
|
||||
(,_if result
|
||||
,expand
|
||||
,(expand-clauses (cdr clauses) rename))))))))
|
||||
|
||||
(if (and (symbol? ellipsis)
|
||||
(list? literals)
|
||||
(every? symbol? literals)
|
||||
(list? rules)
|
||||
(every? (lambda (l) (and (list? l) (= (length l) 2))) rules))
|
||||
(if (member ellipsis literals compare)
|
||||
`(syntax-rules #f ,literals ,@rules)
|
||||
`(syntax-rules ,ellipsis ,literals ,@rules))
|
||||
#f))
|
||||
#f))
|
||||
(define (normalize-form form)
|
||||
(if (and (list? form) (>= (length form) 2))
|
||||
(let ((ellipsis '...)
|
||||
(literals (cadr form))
|
||||
(rules (cddr form)))
|
||||
|
||||
(let ((form (normalize-form form)))
|
||||
(if form
|
||||
(let ((ellipsis (cadr form))
|
||||
(literals (caddr form))
|
||||
(rules (cdddr form)))
|
||||
(let ((clauses (map (lambda (rule) (compile-rule ellipsis literals rule))
|
||||
rules)))
|
||||
`(,_er-macro-transformer
|
||||
(,_lambda (expr rename cmp)
|
||||
,(expand-clauses clauses r)))))
|
||||
(when (symbol? literals)
|
||||
(set! ellipsis literals)
|
||||
(set! literals (car rules))
|
||||
(set! rules (cdr rules)))
|
||||
|
||||
`(,_syntax-error "malformed syntax-rules"))))))
|
||||
(if (and (symbol? ellipsis)
|
||||
(list? literals)
|
||||
(every? symbol? literals)
|
||||
(list? rules)
|
||||
(every? (lambda (l) (and (list? l) (= (length l) 2))) rules))
|
||||
(if (member ellipsis literals compare)
|
||||
`(syntax-rules #f ,literals ,@rules)
|
||||
`(syntax-rules ,ellipsis ,literals ,@rules))
|
||||
#f))
|
||||
#f))
|
||||
|
||||
;;; test code
|
||||
(import (scheme write))
|
||||
(let ((form (normalize-form form)))
|
||||
(if form
|
||||
(let ((ellipsis (cadr form))
|
||||
(literals (caddr form))
|
||||
(rules (cdddr form)))
|
||||
(let ((clauses (map (lambda (rule) (compile-rule ellipsis literals rule))
|
||||
rules)))
|
||||
`(,_er-macro-transformer
|
||||
(,_lambda (expr rename cmp)
|
||||
,(expand-clauses clauses r)))))
|
||||
|
||||
(define-syntax hoge
|
||||
(syntax-rules ()
|
||||
((hoge (a ...) ...) '((a ...) ...))
|
||||
((hoge (a b) ...) '(a ...))
|
||||
((hoge a b ... c . d) 'c)))
|
||||
`(,_syntax-error "malformed syntax-rules"))))))
|
||||
|
||||
(display (hoge (1 2 3) (3 4 5) (5 6 7)))
|
||||
(newline)
|
||||
(display (hoge (a b) (c d) (e f)))
|
||||
(newline)
|
||||
(display (hoge a b c))
|
||||
(newline)
|
||||
(export syntax-rules))
|
||||
|
|
|
|||
Loading…
Reference in New Issue