scsh-0.5/rts/bummed-jar-defrecord.scm

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1995-10-13 23:34:21 -04:00
; Copyright (c) 1993, 1994 Richard Kelsey and Jonathan Rees. See file COPYING.
; Same as jar-defrecord.scm, but field access is "optimized" in a
; brutally unmodular way. The accessors and modifiers are easily
; recognized as inlinable because instead of being produced by the
; usual record-accessor and record-modifier combinators, they're
; defined directly as procedures that do record-ref and record-set!
; with constant indexes. There is no check to make sure that the
; record is a record of the correct type.
; Since the record types are not checked at run time, we use LOOPHOLE
; to at least try to get a little bit of compile-time checking.
(define-syntax define-record-type ;same as in jar-defrecord.scm
(syntax-rules ()
((define-record-type ?id ?type
(?constructor ?arg ...)
(?field . ?field-stuff)
...)
(begin (define ?type (make-record-type '?id '(?field ...)))
(define-constructor ?constructor ?type (?arg :value) ...)
(define-accessors ?type (?field . ?field-stuff) ...)))
((define-record-type ?id ?type
(?constructor ?arg ...)
?pred
?more ...)
(begin (define-record-type ?id ?type
(?constructor ?arg ...)
?more ...)
(define ?pred (record-predicate ?type))))))
(define-syntax define-constructor
(syntax-rules ()
((define-constructor ?constructor ?type (?arg ?arg-type) ...)
(define ?constructor
(loophole (proc (?arg-type ...) ?type)
(record-constructor ?type '(?arg ...)))))))
(define-syntax define-accessors
(lambda (e r c)
(let ((%define-accessor (r 'define-accessor))
(%begin (r 'begin))
(type (cadr e))
(field-specs (cddr e)))
(do ((i 1 (+ i 1))
(field-specs field-specs (cdr field-specs))
(ds '()
(cons `(,%define-accessor ,type ,i ,@(cdar field-specs))
ds)))
((null? field-specs)
`(,%begin ,@ds)))))
(define-accessor begin))
(define-syntax define-accessor
(syntax-rules ()
((define-accessor ?type ?index ?accessor)
(define ?accessor
(loophole (proc (?type) :value)
(lambda (r)
(record-ref (loophole :record r) ?index)))))
((define-accessor ?type ?index ?accessor ?modifier)
(begin (define-accessor ?type ?index ?accessor)
(define ?modifier
(loophole (proc (?type :value) :unspecific)
(lambda (r new)
(record-set! (loophole :record r) ?index new))))))
((define-accessor ?type ?index)
(begin))))