685 lines
24 KiB
Scheme
685 lines
24 KiB
Scheme
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(builtin:define-macro call-with-current-environment
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(builtin:lambda (form env)
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(list (cadr form) env)))
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(builtin:define here
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(call-with-current-environment
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(builtin:lambda (env)
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env)))
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(builtin:define the ; synonym for #'var
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(builtin:lambda (var)
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(make-identifier var here)))
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(builtin:define the-builtin-define (the (builtin:quote builtin:define)))
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(builtin:define the-builtin-lambda (the (builtin:quote builtin:lambda)))
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(builtin:define the-builtin-begin (the (builtin:quote builtin:begin)))
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(builtin:define the-builtin-quote (the (builtin:quote builtin:quote)))
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(builtin:define the-builtin-set! (the (builtin:quote builtin:set!)))
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(builtin:define the-builtin-if (the (builtin:quote builtin:if)))
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(builtin:define the-builtin-define-macro (the (builtin:quote builtin:define-macro)))
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(builtin:define the-define (the (builtin:quote define)))
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(builtin:define the-lambda (the (builtin:quote lambda)))
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(builtin:define the-begin (the (builtin:quote begin)))
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(builtin:define the-quote (the (builtin:quote quote)))
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(builtin:define the-set! (the (builtin:quote set!)))
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(builtin:define the-if (the (builtin:quote if)))
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(builtin:define the-define-macro (the (builtin:quote define-macro)))
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(builtin:define-macro quote
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(builtin:lambda (form env)
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(builtin:if (= (length form) 2)
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(list the-builtin-quote (cadr form))
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(error "illegal quote form" form))))
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(builtin:define-macro if
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(builtin:lambda (form env)
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((builtin:lambda (len)
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(builtin:if (= len 4)
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(cons the-builtin-if (cdr form))
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(builtin:if (= len 3)
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(list the-builtin-if (list-ref form 1) (list-ref form 2) #undefined)
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(error "illegal if form" form))))
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(length form))))
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(builtin:define-macro begin
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(builtin:lambda (form env)
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((builtin:lambda (len)
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(if (= len 1)
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#undefined
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(if (= len 2)
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(cadr form)
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(if (= len 3)
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(cons the-builtin-begin (cdr form))
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(list the-builtin-begin
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(cadr form)
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(cons the-begin (cddr form)))))))
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(length form))))
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(builtin:define-macro set!
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(builtin:lambda (form env)
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(if (= (length form) 3)
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(if (identifier? (cadr form))
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(cons the-builtin-set! (cdr form))
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(error "illegal set! form" form))
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(error "illegal set! form" form))))
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(builtin:define check-formal
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(builtin:lambda (formal)
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(if (null? formal)
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#t
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(if (identifier? formal)
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#t
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(if (pair? formal)
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(if (identifier? (car formal))
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(check-formal (cdr formal))
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#f)
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#f)))))
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(builtin:define-macro lambda
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(builtin:lambda (form env)
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(if (= (length form) 1)
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(error "illegal lambda form" form)
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(if (check-formal (cadr form))
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(list the-builtin-lambda (cadr form) (cons the-begin (cddr form)))
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(error "illegal lambda form" form)))))
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(builtin:define-macro define
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(lambda (form env)
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((lambda (len)
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(if (= len 1)
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(error "illegal define form" form)
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(if (identifier? (cadr form))
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(if (= len 3)
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(cons the-builtin-define (cdr form))
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(error "illegal define form" form))
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(if (pair? (cadr form))
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(list the-define
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(car (cadr form))
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(cons the-lambda (cons (cdr (cadr form)) (cddr form))))
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(error "define: binding to non-varaible object" form)))))
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(length form))))
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(builtin:define-macro define-macro
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(lambda (form env)
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(if (= (length form) 3)
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(if (identifier? (cadr form))
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(cons the-builtin-define-macro (cdr form))
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(error "define-macro: binding to non-variable object" form))
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(error "illegal define-macro form" form))))
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(define-macro syntax-error
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(lambda (form _)
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(apply error (cdr form))))
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(define-macro define-auxiliary-syntax
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(lambda (form _)
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(define message
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(string-append
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"invalid use of auxiliary syntax: '" (symbol->string (cadr form)) "'"))
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(list
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the-define-macro
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(cadr form)
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(list the-lambda '_
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(list (the 'error) message)))))
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(define-auxiliary-syntax else)
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(define-auxiliary-syntax =>)
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(define-auxiliary-syntax unquote)
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(define-auxiliary-syntax unquote-splicing)
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(define-auxiliary-syntax syntax-unquote)
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(define-auxiliary-syntax syntax-unquote-splicing)
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(define-macro let
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(lambda (form env)
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(if (identifier? (cadr form))
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(list
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(list the-lambda '()
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(list the-define (cadr form)
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(cons the-lambda
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(cons (map car (car (cddr form)))
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(cdr (cddr form)))))
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(cons (cadr form) (map cadr (car (cddr form))))))
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(cons
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(cons
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the-lambda
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(cons (map car (cadr form))
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(cddr form)))
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(map cadr (cadr form))))))
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(define-macro and
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(lambda (form env)
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(if (null? (cdr form))
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#t
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(if (null? (cddr form))
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(cadr form)
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(list the-if
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(cadr form)
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(cons (the 'and) (cddr form))
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#f)))))
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(define-macro or
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(lambda (form env)
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(if (null? (cdr form))
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#f
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(let ((tmp (make-identifier 'it env)))
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(list (the 'let)
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(list (list tmp (cadr form)))
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(list the-if
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tmp
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tmp
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(cons (the 'or) (cddr form))))))))
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(define-macro cond
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(lambda (form env)
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(let ((clauses (cdr form)))
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(if (null? clauses)
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#undefined
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(let ((clause (car clauses)))
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(if (and (identifier? (car clause))
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(identifier=? (the 'else) (make-identifier (car clause) env)))
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(cons the-begin (cdr clause))
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(if (null? (cdr clause))
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(let ((tmp (make-identifier 'tmp here)))
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(list (the 'let) (list (list tmp (car clause)))
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(list the-if tmp tmp (cons (the 'cond) (cdr clauses)))))
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(if (and (identifier? (cadr clause))
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(identifier=? (the '=>) (make-identifier (cadr clause) env)))
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(let ((tmp (make-identifier 'tmp here)))
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(list (the 'let) (list (list tmp (car clause)))
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(list the-if tmp
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(list (car (cddr clause)) tmp)
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(cons (the 'cond) (cdr clauses)))))
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(list the-if (car clause)
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(cons the-begin (cdr clause))
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(cons (the 'cond) (cdr clauses)))))))))))
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(define-macro quasiquote
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(lambda (form env)
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(define (quasiquote? form)
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(and (pair? form)
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(identifier? (car form))
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(identifier=? (the 'quasiquote) (make-identifier (car form) env))))
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(define (unquote? form)
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(and (pair? form)
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(identifier? (car form))
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(identifier=? (the 'unquote) (make-identifier (car form) env))))
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(define (unquote-splicing? form)
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(and (pair? form)
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(pair? (car form))
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(identifier? (caar form))
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(identifier=? (the 'unquote-splicing) (make-identifier (caar form) env))))
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(define (qq depth expr)
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(cond
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;; unquote
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((unquote? expr)
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(if (= depth 1)
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(car (cdr expr))
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(list (the 'list)
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(list (the 'quote) (the 'unquote))
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(qq (- depth 1) (car (cdr expr))))))
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;; unquote-splicing
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((unquote-splicing? expr)
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(if (= depth 1)
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(list (the 'append)
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(car (cdr (car expr)))
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(qq depth (cdr expr)))
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(list (the 'cons)
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(list (the 'list)
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(list (the 'quote) (the 'unquote-splicing))
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(qq (- depth 1) (car (cdr (car expr)))))
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(qq depth (cdr expr)))))
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;; quasiquote
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((quasiquote? expr)
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(list (the 'list)
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(list (the 'quote) (the 'quasiquote))
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(qq (+ depth 1) (car (cdr expr)))))
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;; list
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((pair? expr)
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(list (the 'cons)
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(qq depth (car expr))
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(qq depth (cdr expr))))
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;; vector
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((vector? expr)
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(list (the 'list->vector) (qq depth (vector->list expr))))
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;; simple datum
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(else
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(list (the 'quote) expr))))
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(let ((x (cadr form)))
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(qq 1 x))))
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(define-macro let*
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(lambda (form env)
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(let ((bindings (car (cdr form)))
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(body (cdr (cdr form))))
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(if (null? bindings)
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`(,(the 'let) () ,@body)
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`(,(the 'let) ((,(car (car bindings)) ,@(cdr (car bindings))))
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(,(the 'let*) (,@(cdr bindings))
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,@body))))))
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(define-macro letrec
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(lambda (form env)
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`(,(the 'letrec*) ,@(cdr form))))
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(define-macro letrec*
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(lambda (form env)
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(let ((bindings (car (cdr form)))
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(body (cdr (cdr form))))
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(let ((variables (map (lambda (v) `(,v #f)) (map car bindings)))
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(initials (map (lambda (v) `(,(the 'set!) ,@v)) bindings)))
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`(,(the 'let) (,@variables)
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,@initials
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,@body)))))
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(define-macro let-values
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(lambda (form env)
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`(,(the 'let*-values) ,@(cdr form))))
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(define-macro let*-values
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(lambda (form env)
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(let ((formal (car (cdr form)))
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(body (cdr (cdr form))))
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(if (null? formal)
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`(,(the 'let) () ,@body)
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`(,(the 'call-with-values) (,the-lambda () ,@(cdr (car formal)))
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(,(the 'lambda) (,@(car (car formal)))
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(,(the 'let*-values) (,@(cdr formal))
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,@body)))))))
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(define-macro define-values
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(lambda (form env)
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(let ((formal (car (cdr form)))
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(body (cdr (cdr form))))
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(let ((arguments (make-identifier 'arguments here)))
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`(,the-begin
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,@(let loop ((formal formal))
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(if (pair? formal)
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`((,the-define ,(car formal) #undefined) ,@(loop (cdr formal)))
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(if (identifier? formal)
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`((,the-define ,formal #undefined))
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'())))
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(,(the 'call-with-values) (,the-lambda () ,@body)
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(,the-lambda
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,arguments
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,@(let loop ((formal formal) (args arguments))
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(if (pair? formal)
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`((,the-set! ,(car formal) (,(the 'car) ,args)) ,@(loop (cdr formal) `(,(the 'cdr) ,args)))
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(if (identifier? formal)
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`((,the-set! ,formal ,args))
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'()))))))))))
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(define-macro do
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(lambda (form env)
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(let ((bindings (car (cdr form)))
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(test (car (car (cdr (cdr form)))))
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(cleanup (cdr (car (cdr (cdr form)))))
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(body (cdr (cdr (cdr form)))))
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(let ((loop (make-identifier 'loop here)))
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`(,(the 'let) ,loop ,(map (lambda (x) `(,(car x) ,(cadr x))) bindings)
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(,the-if ,test
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(,the-begin
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,@cleanup)
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(,the-begin
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,@body
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(,loop ,@(map (lambda (x) (if (null? (cdr (cdr x))) (car x) (car (cdr (cdr x))))) bindings)))))))))
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(define-macro when
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(lambda (form env)
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(let ((test (car (cdr form)))
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(body (cdr (cdr form))))
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`(,the-if ,test
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(,the-begin ,@body)
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#undefined))))
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(define-macro unless
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(lambda (form env)
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(let ((test (car (cdr form)))
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(body (cdr (cdr form))))
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`(,the-if ,test
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#undefined
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(,the-begin ,@body)))))
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(define-macro case
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(lambda (form env)
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(let ((key (car (cdr form)))
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(clauses (cdr (cdr form))))
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(let ((the-key (make-identifier 'key here)))
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`(,(the 'let) ((,the-key ,key))
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,(let loop ((clauses clauses))
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(if (null? clauses)
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#undefined
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(let ((clause (car clauses)))
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`(,the-if ,(if (and (identifier? (car clause))
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|
|
(identifier=? (the 'else) (make-identifier (car clause) env)))
|
||
|
|
#t
|
||
|
|
`(,(the 'or) ,@(map (lambda (x) `(,(the 'eqv?) ,the-key (,the-quote ,x))) (car clause))))
|
||
|
|
,(if (and (identifier? (cadr clause))
|
||
|
|
(identifier=? (the '=>) (make-identifier (cadr clause) env)))
|
||
|
|
`(,(car (cdr (cdr clause))) ,the-key)
|
||
|
|
`(,the-begin ,@(cdr clause)))
|
||
|
|
,(loop (cdr clauses)))))))))))
|
||
|
|
|
||
|
|
(define-macro parameterize
|
||
|
|
(lambda (form env)
|
||
|
|
(let ((formal (car (cdr form)))
|
||
|
|
(body (cdr (cdr form))))
|
||
|
|
(if (null? formal)
|
||
|
|
`(,the-begin ,@body)
|
||
|
|
(let ((bind (car formal)))
|
||
|
|
`(,(the 'dynamic-bind) ,(car bind) ,(cadr bind)
|
||
|
|
(,the-lambda () (,(the 'parameterize) ,(cdr formal) ,@body))))))))
|
||
|
|
|
||
|
|
(define-macro syntax-quote
|
||
|
|
(lambda (form env)
|
||
|
|
(let ((renames '()))
|
||
|
|
(letrec
|
||
|
|
((rename (lambda (var)
|
||
|
|
(let ((x (assq var renames)))
|
||
|
|
(if x
|
||
|
|
(cadr x)
|
||
|
|
(begin
|
||
|
|
(set! renames `((,var ,(make-identifier var env) (,(the 'make-identifier) ',var ',env)) . ,renames))
|
||
|
|
(rename var))))))
|
||
|
|
(walk (lambda (f form)
|
||
|
|
(cond
|
||
|
|
((identifier? form)
|
||
|
|
(f form))
|
||
|
|
((pair? form)
|
||
|
|
`(,(the 'cons) (walk f (car form)) (walk f (cdr form))))
|
||
|
|
((vector? form)
|
||
|
|
`(,(the 'list->vector) (walk f (vector->list form))))
|
||
|
|
(else
|
||
|
|
`(,(the 'quote) ,form))))))
|
||
|
|
(let ((form (walk rename (cadr form))))
|
||
|
|
`(,(the 'let)
|
||
|
|
,(map cdr renames)
|
||
|
|
,form))))))
|
||
|
|
|
||
|
|
(define-macro syntax-quasiquote
|
||
|
|
(lambda (form env)
|
||
|
|
(let ((renames '()))
|
||
|
|
(letrec
|
||
|
|
((rename (lambda (var)
|
||
|
|
(let ((x (assq var renames)))
|
||
|
|
(if x
|
||
|
|
(cadr x)
|
||
|
|
(begin
|
||
|
|
(set! renames `((,var ,(make-identifier var env) (,(the 'make-identifier) ',var ',env)) . ,renames))
|
||
|
|
(rename var)))))))
|
||
|
|
|
||
|
|
(define (syntax-quasiquote? form)
|
||
|
|
(and (pair? form)
|
||
|
|
(identifier? (car form))
|
||
|
|
(identifier=? (the 'syntax-quasiquote) (make-identifier (car form) env))))
|
||
|
|
|
||
|
|
(define (syntax-unquote? form)
|
||
|
|
(and (pair? form)
|
||
|
|
(identifier? (car form))
|
||
|
|
(identifier=? (the 'syntax-unquote) (make-identifier (car form) env))))
|
||
|
|
|
||
|
|
(define (syntax-unquote-splicing? form)
|
||
|
|
(and (pair? form)
|
||
|
|
(pair? (car form))
|
||
|
|
(identifier? (caar form))
|
||
|
|
(identifier=? (the 'syntax-unquote-splicing) (make-identifier (caar form) env))))
|
||
|
|
|
||
|
|
(define (qq depth expr)
|
||
|
|
(cond
|
||
|
|
;; syntax-unquote
|
||
|
|
((syntax-unquote? expr)
|
||
|
|
(if (= depth 1)
|
||
|
|
(car (cdr expr))
|
||
|
|
(list (the 'list)
|
||
|
|
(list (the 'quote) (the 'syntax-unquote))
|
||
|
|
(qq (- depth 1) (car (cdr expr))))))
|
||
|
|
;; syntax-unquote-splicing
|
||
|
|
((syntax-unquote-splicing? expr)
|
||
|
|
(if (= depth 1)
|
||
|
|
(list (the 'append)
|
||
|
|
(car (cdr (car expr)))
|
||
|
|
(qq depth (cdr expr)))
|
||
|
|
(list (the 'cons)
|
||
|
|
(list (the 'list)
|
||
|
|
(list (the 'quote) (the 'syntax-unquote-splicing))
|
||
|
|
(qq (- depth 1) (car (cdr (car expr)))))
|
||
|
|
(qq depth (cdr expr)))))
|
||
|
|
;; syntax-quasiquote
|
||
|
|
((syntax-quasiquote? expr)
|
||
|
|
(list (the 'list)
|
||
|
|
(list (the 'quote) (the 'quasiquote))
|
||
|
|
(qq (+ depth 1) (car (cdr expr)))))
|
||
|
|
;; list
|
||
|
|
((pair? expr)
|
||
|
|
(list (the 'cons)
|
||
|
|
(qq depth (car expr))
|
||
|
|
(qq depth (cdr expr))))
|
||
|
|
;; vector
|
||
|
|
((vector? expr)
|
||
|
|
(list (the 'list->vector) (qq depth (vector->list expr))))
|
||
|
|
;; identifier
|
||
|
|
((identifier? expr)
|
||
|
|
(rename expr))
|
||
|
|
;; simple datum
|
||
|
|
(else
|
||
|
|
(list (the 'quote) expr))))
|
||
|
|
|
||
|
|
(let ((body (qq 1 (cadr form))))
|
||
|
|
`(,(the 'let)
|
||
|
|
,(map cdr renames)
|
||
|
|
,body))))))
|
||
|
|
|
||
|
|
(define (transformer f)
|
||
|
|
(lambda (form env)
|
||
|
|
(let ((ephemeron1 (make-ephemeron))
|
||
|
|
(ephemeron2 (make-ephemeron)))
|
||
|
|
(letrec
|
||
|
|
((wrap (lambda (var1)
|
||
|
|
(let ((var2 (ephemeron1 var1)))
|
||
|
|
(if var2
|
||
|
|
(cdr var2)
|
||
|
|
(let ((var2 (make-identifier var1 env)))
|
||
|
|
(ephemeron1 var1 var2)
|
||
|
|
(ephemeron2 var2 var1)
|
||
|
|
var2)))))
|
||
|
|
(unwrap (lambda (var2)
|
||
|
|
(let ((var1 (ephemeron2 var2)))
|
||
|
|
(if var1
|
||
|
|
(cdr var1)
|
||
|
|
var2))))
|
||
|
|
(walk (lambda (f form)
|
||
|
|
(cond
|
||
|
|
((identifier? form)
|
||
|
|
(f form))
|
||
|
|
((pair? form)
|
||
|
|
(cons (walk f (car form)) (walk f (cdr form))))
|
||
|
|
((vector? form)
|
||
|
|
(list->vector (walk f (vector->list form))))
|
||
|
|
(else
|
||
|
|
form)))))
|
||
|
|
(let ((form (cdr form)))
|
||
|
|
(walk unwrap (apply f (walk wrap form))))))))
|
||
|
|
|
||
|
|
(define-macro define-syntax
|
||
|
|
(lambda (form env)
|
||
|
|
(let ((formal (car (cdr form)))
|
||
|
|
(body (cdr (cdr form))))
|
||
|
|
(if (pair? formal)
|
||
|
|
`(,(the 'define-syntax) ,(car formal) (,the-lambda ,(cdr formal) ,@body))
|
||
|
|
`(,the-define-macro ,formal (,(the 'transformer) (,the-begin ,@body)))))))
|
||
|
|
|
||
|
|
(define-macro letrec-syntax
|
||
|
|
(lambda (form env)
|
||
|
|
(let ((formal (car (cdr form)))
|
||
|
|
(body (cdr (cdr form))))
|
||
|
|
`(let ()
|
||
|
|
,@(map (lambda (x)
|
||
|
|
`(,(the 'define-syntax) ,(car x) ,(cadr x)))
|
||
|
|
formal)
|
||
|
|
,@body))))
|
||
|
|
|
||
|
|
(define-macro let-syntax
|
||
|
|
(lambda (form env)
|
||
|
|
`(,(the 'letrec-syntax) ,@(cdr form))))
|
||
|
|
|
||
|
|
|
||
|
|
;;; library primitives
|
||
|
|
|
||
|
|
(define (mangle name)
|
||
|
|
(when (null? name)
|
||
|
|
(error "library name should be a list of at least one symbols" name))
|
||
|
|
|
||
|
|
(define (->string n)
|
||
|
|
(cond
|
||
|
|
((symbol? n)
|
||
|
|
(let ((str (symbol->string n)))
|
||
|
|
(string-for-each
|
||
|
|
(lambda (c)
|
||
|
|
(when (or (char=? c #\.) (char=? c #\/))
|
||
|
|
(error "elements of library name may not contain '.' or '/'" n)))
|
||
|
|
str)
|
||
|
|
str))
|
||
|
|
((and (number? n) (exact? n))
|
||
|
|
(number->string n))
|
||
|
|
(else
|
||
|
|
(error "symbol or integer is required" n))))
|
||
|
|
|
||
|
|
(define (join strs delim)
|
||
|
|
(let loop ((res (car strs)) (strs (cdr strs)))
|
||
|
|
(if (null? strs)
|
||
|
|
res
|
||
|
|
(loop (string-append res delim (car strs)) (cdr strs)))))
|
||
|
|
|
||
|
|
(join (map ->string name) "."))
|
||
|
|
|
||
|
|
(define-macro define-library
|
||
|
|
(lambda (form _)
|
||
|
|
(let ((lib (mangle (cadr form)))
|
||
|
|
(body (cddr form)))
|
||
|
|
(or (find-library lib) (make-library lib))
|
||
|
|
(for-each (lambda (expr) (eval expr lib)) body))))
|
||
|
|
|
||
|
|
(define-macro cond-expand
|
||
|
|
(lambda (form _)
|
||
|
|
(letrec
|
||
|
|
((test (lambda (form)
|
||
|
|
(or
|
||
|
|
(eq? form 'else)
|
||
|
|
(and (symbol? form)
|
||
|
|
(memq form (features)))
|
||
|
|
(and (pair? form)
|
||
|
|
(case (car form)
|
||
|
|
((library) (find-library (mangle (cadr form))))
|
||
|
|
((not) (not (test (cadr form))))
|
||
|
|
((and) (let loop ((form (cdr form)))
|
||
|
|
(or (null? form)
|
||
|
|
(and (test (car form)) (loop (cdr form))))))
|
||
|
|
((or) (let loop ((form (cdr form)))
|
||
|
|
(and (pair? form)
|
||
|
|
(or (test (car form)) (loop (cdr form))))))
|
||
|
|
(else #f)))))))
|
||
|
|
(let loop ((clauses (cdr form)))
|
||
|
|
(if (null? clauses)
|
||
|
|
#undefined
|
||
|
|
(if (test (caar clauses))
|
||
|
|
`(,the-begin ,@(cdar clauses))
|
||
|
|
(loop (cdr clauses))))))))
|
||
|
|
|
||
|
|
(define-macro import
|
||
|
|
(lambda (form _)
|
||
|
|
(let ((caddr
|
||
|
|
(lambda (x) (car (cdr (cdr x)))))
|
||
|
|
(prefix
|
||
|
|
(lambda (prefix symbol)
|
||
|
|
(string->symbol
|
||
|
|
(string-append
|
||
|
|
(symbol->string prefix)
|
||
|
|
(symbol->string symbol)))))
|
||
|
|
(getlib
|
||
|
|
(lambda (name)
|
||
|
|
(let ((lib (mangle name)))
|
||
|
|
(if (find-library lib)
|
||
|
|
lib
|
||
|
|
(error "library not found" name))))))
|
||
|
|
(letrec
|
||
|
|
((extract
|
||
|
|
(lambda (spec)
|
||
|
|
(case (car spec)
|
||
|
|
((only rename prefix except)
|
||
|
|
(extract (cadr spec)))
|
||
|
|
(else
|
||
|
|
(getlib spec)))))
|
||
|
|
(collect
|
||
|
|
(lambda (spec)
|
||
|
|
(case (car spec)
|
||
|
|
((only)
|
||
|
|
(let ((alist (collect (cadr spec))))
|
||
|
|
(map (lambda (var) (assq var alist)) (cddr spec))))
|
||
|
|
((rename)
|
||
|
|
(let ((alist (collect (cadr spec)))
|
||
|
|
(renames (map (lambda (x) `((car x) . (cadr x))) (cddr spec))))
|
||
|
|
(map (lambda (s) (or (assq (car s) renames) s)) alist)))
|
||
|
|
((prefix)
|
||
|
|
(let ((alist (collect (cadr spec))))
|
||
|
|
(map (lambda (s) (cons (prefix (caddr spec) (car s)) (cdr s))) alist)))
|
||
|
|
((except)
|
||
|
|
(let ((alist (collect (cadr spec))))
|
||
|
|
(let loop ((alist alist))
|
||
|
|
(if (null? alist)
|
||
|
|
'()
|
||
|
|
(if (memq (caar alist) (cddr spec))
|
||
|
|
(loop (cdr alist))
|
||
|
|
(cons (car alist) (loop (cdr alist))))))))
|
||
|
|
(else
|
||
|
|
(map (lambda (x) (cons x x)) (library-exports (getlib spec))))))))
|
||
|
|
(letrec
|
||
|
|
((import
|
||
|
|
(lambda (spec)
|
||
|
|
(let ((lib (extract spec))
|
||
|
|
(alist (collect spec)))
|
||
|
|
(for-each
|
||
|
|
(lambda (slot)
|
||
|
|
(library-import lib (cdr slot) (car slot)))
|
||
|
|
alist)))))
|
||
|
|
(for-each import (cdr form)))))))
|
||
|
|
|
||
|
|
(define-macro export
|
||
|
|
(lambda (form _)
|
||
|
|
(letrec
|
||
|
|
((collect
|
||
|
|
(lambda (spec)
|
||
|
|
(cond
|
||
|
|
((symbol? spec)
|
||
|
|
`(,spec . ,spec))
|
||
|
|
((and (list? spec) (= (length spec) 3) (eq? (car spec) 'rename))
|
||
|
|
`(,(list-ref spec 1) . ,(list-ref spec 2)))
|
||
|
|
(else
|
||
|
|
(error "malformed export")))))
|
||
|
|
(export
|
||
|
|
(lambda (spec)
|
||
|
|
(let ((slot (collect spec)))
|
||
|
|
(library-export (car slot) (cdr slot))))))
|
||
|
|
(for-each export (cdr form)))))
|
||
|
|
|
||
|
|
(export define lambda quote set! if begin define-macro
|
||
|
|
let let* letrec letrec*
|
||
|
|
let-values let*-values define-values
|
||
|
|
quasiquote unquote unquote-splicing
|
||
|
|
and or
|
||
|
|
cond case else =>
|
||
|
|
do when unless
|
||
|
|
parameterize
|
||
|
|
define-syntax
|
||
|
|
syntax-quote syntax-unquote
|
||
|
|
syntax-quasiquote syntax-unquote-splicing
|
||
|
|
let-syntax letrec-syntax
|
||
|
|
syntax-error)
|