File size: 11,271 Bytes
3dcad1f |
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 |
;;; syntactic.scm --- Syntactic support for R6RS records
;; Copyright (C) 2010 Free Software Foundation, Inc.
;;
;; This library is free software; you can redistribute it and/or
;; modify it under the terms of the GNU Lesser General Public
;; License as published by the Free Software Foundation; either
;; version 3 of the License, or (at your option) any later version.
;;
;; This library 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
;; Lesser General Public License for more details.
;;
;; You should have received a copy of the GNU Lesser General Public
;; License along with this library; if not, write to the Free Software
;; Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
(library (rnrs records syntactic (6))
(export define-record-type
record-type-descriptor
record-constructor-descriptor)
(import (only (guile) and=> gensym)
(rnrs base (6))
(rnrs conditions (6))
(rnrs exceptions (6))
(rnrs hashtables (6))
(rnrs lists (6))
(rnrs records procedural (6))
(rnrs syntax-case (6))
(only (srfi :1) take))
(define record-type-registry (make-eq-hashtable))
(define (guess-constructor-name record-name)
(string->symbol (string-append "make-" (symbol->string record-name))))
(define (guess-predicate-name record-name)
(string->symbol (string-append (symbol->string record-name) "?")))
(define (register-record-type name rtd rcd)
(hashtable-set! record-type-registry name (cons rtd rcd)))
(define (lookup-record-type-descriptor name)
(and=> (hashtable-ref record-type-registry name #f) car))
(define (lookup-record-constructor-descriptor name)
(and=> (hashtable-ref record-type-registry name #f) cdr))
(define-syntax define-record-type
(lambda (stx)
(syntax-case stx ()
((_ (record-name constructor-name predicate-name) record-clause ...)
#'(define-record-type0
(record-name constructor-name predicate-name)
record-clause ...))
((_ record-name record-clause ...)
(let* ((record-name-sym (syntax->datum #'record-name))
(constructor-name
(datum->syntax
#'record-name (guess-constructor-name record-name-sym)))
(predicate-name
(datum->syntax
#'record-name (guess-predicate-name record-name-sym))))
#`(define-record-type0
(record-name #,constructor-name #,predicate-name)
record-clause ...))))))
(define (sequence n)
(define (seq-inner n) (if (= n 0) '(0) (cons n (seq-inner (- n 1)))))
(reverse (seq-inner n)))
(define (number-fields fields)
(define (number-fields-inner fields counter)
(if (null? fields)
'()
(cons (cons fields counter)
(number-fields-inner (cdr fields) (+ counter 1)))))
(number-fields-inner fields 0))
(define (process-fields record-name fields)
(define (wrap x) (datum->syntax record-name x))
(define (id->string x)
(symbol->string (syntax->datum x)))
(define record-name-str (id->string record-name))
(define (guess-accessor-name field-name)
(wrap
(string->symbol (string-append
record-name-str "-" (id->string field-name)))))
(define (guess-mutator-name field-name)
(wrap
(string->symbol
(string-append
record-name-str "-" (id->string field-name) "-set!"))))
(define (f x)
(syntax-case x (immutable mutable)
[(immutable name)
(list (wrap `(immutable ,(syntax->datum #'name)))
(guess-accessor-name #'name)
#f)]
[(immutable name accessor)
(list (wrap `(immutable ,(syntax->datum #'name))) #'accessor #f)]
[(mutable name)
(list (wrap `(mutable ,(syntax->datum #'name)))
(guess-accessor-name #'name)
(guess-mutator-name #'name))]
[(mutable name accessor mutator)
(list (wrap `(mutable ,(syntax->datum #'name))) #'accessor #'mutator)]
[name
(identifier? #'name)
(list (wrap `(immutable ,(syntax->datum #'name)))
(guess-accessor-name #'name)
#f)]
[else
(syntax-violation 'define-record-type "invalid field specifier" x)]))
(map f fields))
(define-syntax define-record-type0
(lambda (stx)
(define *unspecified* (cons #f #f))
(define (unspecified? obj)
(eq? *unspecified* obj))
(syntax-case stx ()
((_ (record-name constructor-name predicate-name) record-clause ...)
(let loop ((_fields *unspecified*)
(_parent *unspecified*)
(_protocol *unspecified*)
(_sealed *unspecified*)
(_opaque *unspecified*)
(_nongenerative *unspecified*)
(_constructor *unspecified*)
(_parent-rtd *unspecified*)
(record-clauses #'(record-clause ...)))
(syntax-case record-clauses
(fields parent protocol sealed opaque nongenerative
constructor parent-rtd)
[()
(let* ((fields (if (unspecified? _fields) '() _fields))
(field-names (list->vector (map car fields)))
(field-accessors
(fold-left (lambda (lst x c)
(cons #`(define #,(cadr x)
(record-accessor record-name #,c))
lst))
'() fields (sequence (length fields))))
(field-mutators
(fold-left (lambda (lst x c)
(if (caddr x)
(cons #`(define #,(caddr x)
(record-mutator record-name
#,c))
lst)
lst))
'() fields (sequence (length fields))))
(parent-cd (cond ((not (unspecified? _parent))
#`(record-constructor-descriptor
#,_parent))
((not (unspecified? _parent-rtd))
(cadr _parent-rtd))
(else #f)))
(parent-rtd (cond ((not (unspecified? _parent))
#`(record-type-descriptor #,_parent))
((not (unspecified? _parent-rtd))
(car _parent-rtd))
(else #f)))
(protocol (if (unspecified? _protocol) #f _protocol))
(uid (if (unspecified? _nongenerative) #f _nongenerative))
(sealed? (if (unspecified? _sealed) #f _sealed))
(opaque? (if (unspecified? _opaque) #f _opaque)))
#`(begin
(define record-name
(make-record-type-descriptor
(quote record-name)
#,parent-rtd #,uid #,sealed? #,opaque?
#,field-names))
(define constructor-name
(record-constructor
(make-record-constructor-descriptor
record-name #,parent-cd #,protocol)))
(define dummy
(let ()
(register-record-type
(quote record-name)
record-name (make-record-constructor-descriptor
record-name #,parent-cd #,protocol))
'dummy))
(define predicate-name (record-predicate record-name))
#,@field-accessors
#,@field-mutators))]
[((fields record-fields ...) . rest)
(if (unspecified? _fields)
(loop (process-fields #'record-name #'(record-fields ...))
_parent _protocol _sealed _opaque _nongenerative
_constructor _parent-rtd #'rest)
(raise (make-assertion-violation)))]
[((parent parent-name) . rest)
(if (not (unspecified? _parent-rtd))
(raise (make-assertion-violation))
(if (unspecified? _parent)
(loop _fields #'parent-name _protocol _sealed _opaque
_nongenerative _constructor _parent-rtd #'rest)
(raise (make-assertion-violation))))]
[((protocol expression) . rest)
(if (unspecified? _protocol)
(loop _fields _parent #'expression _sealed _opaque
_nongenerative _constructor _parent-rtd #'rest)
(raise (make-assertion-violation)))]
[((sealed sealed?) . rest)
(if (unspecified? _sealed)
(loop _fields _parent _protocol #'sealed? _opaque
_nongenerative _constructor _parent-rtd #'rest)
(raise (make-assertion-violation)))]
[((opaque opaque?) . rest)
(if (unspecified? _opaque)
(loop _fields _parent _protocol _sealed #'opaque?
_nongenerative _constructor _parent-rtd #'rest)
(raise (make-assertion-violation)))]
[((nongenerative) . rest)
(if (unspecified? _nongenerative)
(loop _fields _parent _protocol _sealed _opaque
#`(quote #,(datum->syntax #'record-name (gensym)))
_constructor _parent-rtd #'rest)
(raise (make-assertion-violation)))]
[((nongenerative uid) . rest)
(if (unspecified? _nongenerative)
(loop _fields _parent _protocol _sealed
_opaque #''uid _constructor
_parent-rtd #'rest)
(raise (make-assertion-violation)))]
[((parent-rtd rtd cd) . rest)
(if (not (unspecified? _parent))
(raise (make-assertion-violation))
(if (unspecified? _parent-rtd)
(loop _fields _parent _protocol _sealed _opaque
_nongenerative _constructor #'(rtd cd)
#'rest)
(raise (make-assertion-violation))))]))))))
(define-syntax record-type-descriptor
(lambda (stx)
(syntax-case stx ()
((_ name) #`(lookup-record-type-descriptor
#,(datum->syntax
stx (list 'quote (syntax->datum #'name))))))))
(define-syntax record-constructor-descriptor
(lambda (stx)
(syntax-case stx ()
((_ name) #`(lookup-record-constructor-descriptor
#,(datum->syntax
stx (list 'quote (syntax->datum #'name))))))))
)
|