ikarus/scheme/ikarus.records.procedural.ss

517 lines
18 KiB
Scheme

;;; Ikarus Scheme -- A compiler for R6RS Scheme.
;;; Copyright (C) 2006,2007 Abdulaziz Ghuloum
;;;
;;; This program is free software: you can redistribute it and/or modify
;;; it under the terms of the GNU General Public License version 3 as
;;; published by the Free Software Foundation.
;;;
;;; This program is distributed in the hope that it will be useful, but
;;; WITHOUT ANY WARRANTY; without even the implied warranty of
;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
;;; General Public License for more details.
;;;
;;; You should have received a copy of the GNU General Public License
;;; along with this program. If not, see <http://www.gnu.org/licenses/>.
(library (ikarus records procedural)
(export
make-record-type-descriptor record-type-descriptor?
make-record-constructor-descriptor record-accessor
record-mutator record-constructor record-predicate record?
record-rtd record-type-name record-type-parent record-type-uid
record-type-generative? record-type-sealed? record-type-opaque?
record-type-field-names record-field-mutable? rtd-subtype? rtd?)
(import
(except (ikarus)
record-constructor record-predicate record? record-type-name
record-type-parent record-type-descriptor? record-rtd
record-type-uid record-type-sealed? record-type-opaque?
record-type-generative? make-record-type-descriptor
make-record-constructor-descriptor record-accessor
record-mutator
record-type-field-names record-field-mutable?
rtd? rtd-subtype?)
(ikarus system $structs))
(define-struct rtd
(name size old-fields printer-proc symbol parent sealed? opaque? uid fields))
(define rtd-alist '())
(define (intern-rtd! uid rtd)
(set! rtd-alist (cons (cons uid rtd) rtd-alist)))
(define (lookup-rtd uid)
(cond
[(assq uid rtd-alist) => cdr]
[else #f]))
(define (record-type-descriptor? x) (rtd? x))
(define (record? x)
(and ($struct? x)
(let ([rtd ($struct-rtd x)])
(and (rtd? rtd)
(not (rtd-opaque? rtd))))))
(define (record-rtd x)
(if ($struct? x)
(let ([rtd ($struct-rtd x)])
(if (rtd? rtd)
(if (not (rtd-opaque? rtd))
rtd
(die 'record-rtd "record is opaque"))
(die 'record-rtd "not a record" x)))
(die 'record-rtd "not a record" x)))
(define (record-type-name x)
(if (rtd? x)
(rtd-name x)
(die 'record-type-name "not an rtd" x)))
(define (record-type-parent x)
(if (rtd? x)
(rtd-parent x)
(die 'record-type-parent "not an rtd" x)))
(define (record-type-uid x)
(if (rtd? x)
(rtd-uid x)
(die 'record-type-uid "not an rtd" x)))
(define (record-type-sealed? x)
(if (rtd? x)
(rtd-sealed? x)
(die 'record-type-sealed? "not an rtd" x)))
(define (record-type-opaque? x)
(if (rtd? x)
(rtd-opaque? x)
(die 'record-type-opaque? "not an rtd" x)))
(define (record-type-generative? x)
(if (rtd? x)
(not (rtd-sealed? x))
(die 'record-type-generative? "not an rtd" x)))
(define (record-type-field-names x)
(if (rtd? x)
(let ([v (rtd-fields x)])
(let ([n (vector-length v)])
(let f ([x (make-vector n)] [v v] [n n] [i 0])
(if (= i n)
x
(begin
(vector-set! x i (cdr (vector-ref v i)))
(f x v n (fxadd1 i)))))))
(die 'record-type-field-names "not an rtd" x)))
(module (make-record-type-descriptor)
(define who 'make-record-type-descriptor)
(define (make-rtd-aux name parent uid sealed? opaque?
parent-size fields)
(make-rtd name (+ parent-size (vector-length fields))
#f #f #f parent sealed? opaque? uid fields))
(define (convert-fields sv)
(unless (vector? sv)
(die who "invalid fields argument" sv))
(let ([n2 (vector-length sv)])
(let ([v (make-vector n2)])
(let f ([i 0])
(unless (= i n2)
(let ([x (vector-ref sv i)])
(if (pair? x)
(let ([m/u (car x)] [x (cdr x)])
(if (pair? x)
(let ([name (car x)])
(unless (and (null? (cdr x)) (symbol? name))
(die who "invalid fields argument" sv))
(vector-set! v i
(cons (case m/u
[(mutable) #t]
[(immutable) #f]
[else
(die who "invalid fields argument" sv)])
name)))
(die who "invalid fields argument" sv)))
(die who "invalid fields argument" sv)))
(f (add1 i))))
v)))
(define generate-rtd
(lambda (name parent uid sealed? opaque? fields)
(cond
[(rtd? parent)
(when (rtd-sealed? parent)
(die who "cannot extend sealed parent" parent))
(make-rtd-aux name parent uid sealed?
(or opaque? (rtd-opaque? parent))
(rtd-size parent)
(convert-fields fields))]
[(eqv? parent #f)
(make-rtd-aux name parent uid sealed? opaque? 0
(convert-fields fields))]
[else (die who "not a valid parent" parent)])))
(define (same-fields-as-rtd? fields rtd)
(let* ([fv (rtd-fields rtd)]
[n (vector-length fv)])
(and (vector? fields)
(= (vector-length fields) n)
(let f ([i 0])
(or (= i n)
(let ([a (vector-ref fields i)]
[b (vector-ref fv i)])
(and
(pair? a)
(case (car a)
[(mutable) (eqv? (car b) #t)]
[(immutable) (eqv? (car b) #f)]
[else #f])
(let ([a (cdr a)])
(and (pair? a)
(null? (cdr a))
(eq? (car a) (cdr b))))
(f (+ i 1)))))))))
(define make-nongenerative-rtd
(lambda (name parent uid sealed? opaque? fields)
(cond
[(lookup-rtd uid) =>
(lambda (rtd)
(unless
(and ; must not check name!
; (eqv? name (rtd-name rtd))
(eqv? parent (rtd-parent rtd))
(eqv? sealed? (rtd-sealed? rtd))
(eqv? opaque? (rtd-opaque? rtd))
(same-fields-as-rtd? fields rtd))
(die who "arguments not equivalent to those in an existing rtd"
parent sealed? opaque? fields))
rtd)]
[else
(let ([rtd (generate-rtd name parent uid sealed? opaque? fields)])
(intern-rtd! uid rtd)
rtd)])))
(define make-record-type-descriptor
(lambda (name parent uid sealed? opaque? fields)
(unless (symbol? name)
(die who "not a valid record type name" name))
(unless (boolean? sealed?)
(die who "not a valid sealed? argument" sealed?))
(unless (boolean? opaque?)
(die who "not a valid opaque? argument" opaque?))
(cond
[(symbol? uid)
(make-nongenerative-rtd name parent uid sealed? opaque? fields)]
[(eqv? uid #f)
(generate-rtd name parent uid sealed? opaque? fields)]
[else (die who "not a valid uid" uid)]))))
(define-struct rcd (rtd prcd proc))
(define (is-parent-of? prtd rtd)
(let ([p (rtd-parent rtd)])
(cond
[(eq? p prtd) #t]
[(not p) #f]
[else (is-parent-of? prtd p)])))
(define (rtd-subtype? rtd parent-rtd)
(unless (rtd? rtd)
(die 'rtd-subtype? "not an rtd" rtd))
(unless (rtd? parent-rtd)
(die 'rtd-substype? "not an rtd" parent-rtd))
(or (eq? rtd parent-rtd)
(is-parent-of? parent-rtd rtd)))
(define make-record-constructor-descriptor
(lambda (rtd prcd protocol)
(define who 'make-record-constructor-descriptor)
(unless (rtd? rtd)
(die who "not a record type descriptor" rtd))
(unless (or (not protocol) (procedure? protocol))
(die who "invalid protocol" protocol))
(let ([prtd (rtd-parent rtd)])
(cond
[(not prcd)
(make-rcd rtd #f protocol)]
[(rcd? prcd)
(unless (is-parent-of? (rcd-rtd prcd) rtd)
(die who "descriptor does not apply"
prcd rtd))
(make-rcd rtd prcd protocol)]
[else
(die who "not a valid record constructor descriptor" prcd)]))))
(define (record-constructor rcd)
(define who 'record-constructor)
(define (split all-fields n)
(let f ([ls all-fields] [n n])
(if (zero? n)
(values '() ls)
(if (pair? ls)
(let-values ([(m p) (f (cdr ls) (- n 1))])
(values (cons (car ls) m) p))
(die 'record-condtructor "insufficient arguments"
all-fields)))))
(define (constructor main-rtd size prcd proto)
(define (fill i r flds f*)
(cond
[(null? flds)
(if (null? f*)
r
(fill i r (car f*) (cdr f*)))]
[else
($struct-set! r i (car flds))
(fill (add1 i) r (cdr flds) f*)]))
(if (not prcd) ;;; base
(let ([n (rtd-size main-rtd)])
(define-syntax expand-setters
(syntax-rules ()
[(_ r idx) #f]
[(_ r idx a0 a* ...)
(begin
($struct-set! r idx a0)
(expand-setters r (+ idx 1) a* ...))]))
(define-syntax expand-constructor
(syntax-rules (default)
[(_ f* default)
(lambda flds
(unless (= (length flds) size)
(apply die
'a-record-constructor
(format
"expected ~a args, got ~a instead"
n (length flds))
flds))
(let ([r ($make-struct main-rtd n)])
(fill 0 r flds f*)))]
[(_ f* (args ...))
(lambda (args ...)
(let ([r ($make-struct main-rtd n)])
(expand-setters r 0 args ...)
(if (null? f*)
r
(fill (length '(args ...)) r (car f*) (cdr f*)))))]))
(define-syntax expand-one-case
(syntax-rules ()
[(_ arg-case)
(if proto
(lambda (f*)
(let ([a-record-constructor
(expand-constructor f* arg-case)])
(proto a-record-constructor)))
(lambda (f*)
(let ([a-record-constructor
(expand-constructor f* arg-case)])
a-record-constructor)))]))
(case size
[(0) (expand-one-case ())]
[(1) (expand-one-case (f0))]
[(2) (expand-one-case (f0 f1))]
[(3) (expand-one-case (f0 f1 f2))]
[(4) (expand-one-case (f0 f1 f2 f3))]
[else (expand-one-case default)]))
(let ([pprcd (rcd-prcd prcd)]
[sz (rtd-size (rcd-rtd prcd))])
(let ([p (constructor main-rtd sz pprcd (rcd-proc prcd))]
[n (- size sz)]
[protocol
(if proto
proto
(lambda (new)
(let ([a-record-constructor
(lambda all-fields
(let-values ([(parent-fields myfields)
(split all-fields
(- (length all-fields)
(- size sz)))])
(apply (apply new parent-fields)
myfields)))])
a-record-constructor)))])
(lambda (f*)
(protocol
(lambda fmls
(lambda flds
(unless (= (length flds) n)
(apply die
'a-record-constructor
(format
"expected ~a args, got ~a instead"
n (length flds))
flds))
(apply (p (cons flds f*)) fmls)))))))))
(unless (rcd? rcd)
(die who "not a record constructor descriptor" rcd))
(let ([rtd (rcd-rtd rcd)]
[prcd (rcd-prcd rcd)]
[proto (rcd-proc rcd)])
((constructor rtd (rtd-size rtd) prcd proto) '())))
(define (record-accessor rtd k)
(define who 'record-accessor)
(unless (rtd? rtd)
(die who "not an rtd" rtd))
(unless (and (fixnum? k) (fx>= k 0))
(die who "not a valid index" k))
(let ([sz (rtd-size rtd)]
[p (rtd-parent rtd)])
(let ([i (if p (+ k (rtd-size p)) k)])
(unless (fx< i sz)
(die who "not a valid index" k))
(let ([a-record-accessor
(lambda (x)
(cond
[($struct/rtd? x rtd) ($struct-ref x i)]
[($struct? x)
(let ([xrtd ($struct-rtd x)])
(unless (rtd? xrtd)
(die who "invalid type" x rtd))
(let f ([prtd (rtd-parent xrtd)] [rtd rtd] [x x] [i i])
(cond
[(eq? prtd rtd) ($struct-ref x i)]
[(not prtd)
(die who "invalid type" x rtd)]
[else (f (rtd-parent prtd) rtd x i)])))]
[else (die who "invalid type" x rtd)]))])
a-record-accessor))))
(define (record-mutator rtd k)
(define who 'record-mutator)
(unless (rtd? rtd)
(die who "not an rtd" rtd))
(unless (and (fixnum? k) (fx>= k 0))
(die who "not a valid index" k))
(let ([sz (rtd-size rtd)]
[p (rtd-parent rtd)])
(let ([i (if p (+ k (rtd-size p)) k)])
(unless (fx< i sz)
(die who "not a valid index" k))
(unless (car (vector-ref (rtd-fields rtd) k))
(die who "field is not mutable" k rtd))
(let ([a-record-mutator
(lambda (x v)
(cond
[($struct/rtd? x rtd) ($struct-set! x i v)]
[($struct? x)
(let ([xrtd ($struct-rtd x)])
(unless (rtd? xrtd)
(die who "invalid type" x rtd))
(let f ([prtd (rtd-parent xrtd)] [rtd rtd] [x x] [i i] [v v])
(cond
[(eq? prtd rtd) ($struct-set! x i v)]
[(not prtd)
(die who "invalid type" x rtd)]
[else (f (rtd-parent prtd) rtd x i v)])))]
[else (die who "invalid type" x rtd)]))])
a-record-mutator))))
(define (record-predicate rtd)
(define who 'record-predicate)
(unless (rtd? rtd)
(die who "not an rtd" rtd))
(let ([sz (rtd-size rtd)]
[p (rtd-parent rtd)])
(let ([a-record-predicate
(lambda (x)
(cond
[($struct/rtd? x rtd) #t]
[($struct? x)
(let ([xrtd ($struct-rtd x)])
(and (rtd? xrtd)
(let f ([prtd (rtd-parent xrtd)] [rtd rtd])
(cond
[(eq? prtd rtd) #t]
[(not prtd) #f]
[else (f (rtd-parent prtd) rtd)]))))]
[else #f]))])
a-record-predicate)))
(define (record-field-mutable? rtd k)
(define who 'record-field-mutable?)
(unless (rtd? rtd)
(die who "not an rtd" rtd))
(unless (and (fixnum? k) (fx>= k 0))
(die who "not a valid index" k))
(let ([sz (rtd-size rtd)]
[p (rtd-parent rtd)])
(let ([i (if p (+ k (rtd-size p)) k)])
(unless (fx< i sz)
(die who "not a valid index" k))
(car (vector-ref (rtd-fields rtd) k)))))
(set-rtd-printer! (type-descriptor rtd)
(lambda (x p)
(display (format "#<record-type-descriptor ~s>" (rtd-name x)) p)))
(set-rtd-printer! (type-descriptor rcd)
(lambda (x p)
(display (format "#<record-constructor-descriptor ~s>"
(rtd-name (rcd-rtd x))) p)))
)
#!eof
rtd0 fields=4
proto0 =
(lambda (n)
(lambda (p0-fmls ...)
(n f0 f1 f2 f3)))
rtd1 fields=2
proto1 =
(lambda (n)
(lambda (p1-fmls ...)
((n p0-acts ...) f4 f5)))
rtd2 fields=1
proto2 =
(lambda (n)
(lambda (p2-fmls ...)
((n p1-acts ...) f6)))
(record-constructor rcd2)
==
(proto2 (lambda p1-fml*
(lambda (f6)
(apply (proto1 (lambda p0-fml*
(lambda (f4 f5)
(apply (proto0 (lambda (f0 f1 f2 f3)
($record rtd2 f0 f1 f2 f3 f4 f5 f6)))
p0-fml*))))
p1-fml*))))
new0 = (lambda (f0 f1 f2 f3 f4 f5 f6)
($record rtd2 f0 f1 f2 f3 f4 f5 f6))
(record-constructor rcd2)
==
(proto2 (lambda p1-fml*
(lambda (f6)
(apply (proto1 (lambda p0-fml*
(lambda (f4 f5)
(apply (proto0 (lambda (f0 f1 f2 f3)
(new0 f0 f1 f2 f3 f4 f5 f6)))
p0-fml*))))
p1-fml*))))