mirror of
https://git.savannah.gnu.org/git/guile.git
synced 2025-05-03 13:20:26 +02:00
47c8983f08
* module/oop/goops.scm (method): Reimplement as a hygienic macro. This seriously took me like 6 hours to figure out. Allows for lexical specializers: (let ((<x> ...)) (define-method (foo (arg <x>)) ...)). * module/oop/goops/compile.scm (next-method?, compile-make-procedure): Remove these, as `method' does it all now, hygienically.
80 lines
2.9 KiB
Scheme
80 lines
2.9 KiB
Scheme
;;;; Copyright (C) 1999, 2001, 2006 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 2.1 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
|
||
;;;;
|
||
|
||
|
||
;; There are circularities here; you can't import (oop goops compile)
|
||
;; before (oop goops). So when compiling, make sure that things are
|
||
;; kosher.
|
||
(eval-when (compile) (resolve-module '(oop goops)))
|
||
|
||
(define-module (oop goops compile)
|
||
:use-module (oop goops)
|
||
:use-module (oop goops util)
|
||
:export (compute-cmethod)
|
||
:no-backtrace
|
||
)
|
||
|
||
;;;
|
||
;;; Method entries
|
||
;;;
|
||
|
||
(define code-table-lookup
|
||
(letrec ((check-entry (lambda (entry types)
|
||
(if (null? types)
|
||
(and (not (struct? (car entry)))
|
||
entry)
|
||
(and (eq? (car entry) (car types))
|
||
(check-entry (cdr entry) (cdr types)))))))
|
||
(lambda (code-table types)
|
||
(cond ((null? code-table) #f)
|
||
((check-entry (car code-table) types))
|
||
(else (code-table-lookup (cdr code-table) types))))))
|
||
|
||
(define (compute-cmethod methods types)
|
||
(or (code-table-lookup (slot-ref (car methods) 'code-table) types)
|
||
(let* ((method (car methods))
|
||
(cmethod (compile-method methods types))
|
||
(entry (append types cmethod)))
|
||
(slot-set! method 'code-table
|
||
(cons entry (slot-ref method 'code-table)))
|
||
cmethod)))
|
||
|
||
;;;
|
||
;;; Compiling next methods into method bodies
|
||
;;;
|
||
|
||
;;; So, for the reader: there basic idea is that, given that the
|
||
;;; semantics of `next-method' depend on the concrete types being
|
||
;;; dispatched, why not compile a specific procedure to handle each type
|
||
;;; combination that we see at runtime.
|
||
;;;
|
||
;;; In theory we can do much better than a bytecode compilation, because
|
||
;;; we know the *exact* types of the arguments. It's ideal for native
|
||
;;; compilation. A task for the future.
|
||
;;;
|
||
;;; I think this whole generic application mess would benefit from a
|
||
;;; strict MOP.
|
||
|
||
(define (compile-method methods types)
|
||
(let ((make-procedure (slot-ref (car methods) 'make-procedure)))
|
||
(if make-procedure
|
||
(make-procedure
|
||
(if (null? methods)
|
||
(lambda args
|
||
(no-next-method (method-generic-function (car methods)) args))
|
||
(compute-cmethod (cdr methods) types)))
|
||
(method-procedure (car methods)))))
|