-;;; installed-scm-file
-
-;;;; Copyright (C) 1998,1999,2000,2001,2002, 2003, 2006, 2009, 2010, 2011, 2014, 2015 Free Software Foundation, Inc.
+;;;; goops.scm -- The Guile Object-Oriented Programming System
+;;;;
+;;;; Copyright (C) 1998-2003,2006,2009-2011,2013-2015 Free Software Foundation, Inc.
;;;; Copyright (C) 1993-1998 Erick Gallesio - I3S-CNRS/ESSI <eg@unice.fr>
;;;;
;;;; This library is free software; you can redistribute it and/or
(define-module (oop goops)
#:use-module (srfi srfi-1)
#:use-module (ice-9 match)
- #:use-module (oop goops util)
+ #:use-module ((language tree-il primitives)
+ :select (add-interesting-primitive!))
#:export-syntax (define-class class standard-define-class
- define-generic define-accessor define-method
- define-extended-generic define-extended-generics
- method)
- #:export (is-a? class-of
- ensure-metaclass ensure-metaclass-with-supers
- make-class
- make-generic ensure-generic
- make-extended-generic
- make-accessor ensure-accessor
- add-method!
- class-slot-ref class-slot-set! slot-unbound slot-missing
- slot-definition-name slot-definition-options
- slot-definition-allocation
- slot-definition-getter slot-definition-setter
- slot-definition-accessor
- slot-definition-init-value slot-definition-init-form
- slot-definition-init-thunk slot-definition-init-keyword
- slot-init-function class-slot-definition
- method-source
- compute-cpl compute-std-cpl compute-get-n-set compute-slots
- compute-getter-method compute-setter-method
- allocate-instance initialize make-instance make
- no-next-method no-applicable-method no-method
- change-class update-instance-for-different-class
- shallow-clone deep-clone
- class-redefinition
- apply-generic apply-method apply-methods
- compute-applicable-methods %compute-applicable-methods
- method-more-specific? sort-applicable-methods
- class-subclasses class-methods
- goops-error
- min-fixnum max-fixnum
- ;;; *fixme* Should go into goops.c
- instance? slot-ref-using-class
- slot-set-using-class! slot-bound-using-class?
- slot-exists-using-class? slot-ref slot-set! slot-bound?
- class-name class-direct-supers class-direct-subclasses
- class-direct-methods class-direct-slots class-precedence-list
- class-slots
- generic-function-name
- generic-function-methods method-generic-function
- method-specializers method-formals
- primitive-generic-generic enable-primitive-generic!
- method-procedure accessor-method-slot-definition
- slot-exists? make find-method get-keyword))
-
-(define *goops-module* (current-module))
-
-;; First initialize the builtin part of GOOPS
-(eval-when (expand load eval)
- (%init-goops-builtins))
-
+ define-generic define-accessor define-method
+ define-extended-generic define-extended-generics
+ method)
+ #:export ( ;; The root of everything.
+ <top>
+ <class> <object>
+
+ ;; Slot types.
+ <slot>
+ <foreign-slot> <protected-slot> <hidden-slot> <opaque-slot>
+ <read-only-slot> <self-slot> <protected-opaque-slot>
+ <protected-hidden-slot> <protected-read-only-slot>
+ <scm-slot> <int-slot> <float-slot> <double-slot>
+
+ ;; Methods are implementations of generic functions.
+ <method> <accessor-method>
+
+ ;; Applicable objects, either procedures or applicable structs.
+ <procedure-class> <applicable>
+ <procedure> <primitive-generic>
+
+ ;; Applicable structs.
+ <applicable-struct-class> <applicable-struct-with-setter-class>
+ <applicable-struct> <applicable-struct-with-setter>
+ <generic> <extended-generic>
+ <generic-with-setter> <extended-generic-with-setter>
+ <accessor> <extended-accessor>
+
+ ;; Types with their own allocated typecodes.
+ <boolean> <char> <list> <pair> <null> <string> <symbol>
+ <vector> <bytevector> <uvec> <foreign> <hashtable>
+ <fluid> <dynamic-state> <frame> <vm> <vm-continuation>
+ <keyword>
+
+ ;; Numbers.
+ <number> <complex> <real> <integer> <fraction>
+
+ ;; Unknown.
+ <unknown>
+
+ ;; Particular SMOB data types. All SMOB types have
+ ;; corresponding classes, which may be obtained via class-of,
+ ;; once you have an instance. Perhaps FIXME to provide a
+ ;; smob-type-name->class procedure.
+ <arbiter> <promise> <thread> <mutex> <condition-variable>
+ <regexp> <hook> <bitvector> <random-state> <async>
+ <directory> <array> <character-set>
+ <dynamic-object> <guardian> <macro>
+
+ ;; Modules.
+ <module>
+
+ ;; Ports.
+ <port> <input-port> <output-port> <input-output-port>
+
+ ;; Like SMOB types, all port types have their own classes,
+ ;; which can be accessed via `class-of' once you have an
+ ;; instance. Here we export bindings just for file ports.
+ <file-port>
+ <file-input-port> <file-output-port> <file-input-output-port>
+
+ is-a? class-of
+ ensure-metaclass ensure-metaclass-with-supers
+ make-class
+ make-generic ensure-generic
+ make-extended-generic
+ make-accessor ensure-accessor
+ add-method!
+ class-slot-ref class-slot-set! slot-unbound slot-missing
+ slot-definition-name slot-definition-options
+ slot-definition-allocation
+
+ slot-definition-getter slot-definition-setter
+ slot-definition-accessor
+ slot-definition-init-value slot-definition-init-form
+ slot-definition-init-thunk slot-definition-init-keyword
+ slot-init-function class-slot-definition
+ method-source
+ compute-cpl compute-std-cpl compute-get-n-set compute-slots
+ compute-getter-method compute-setter-method
+ allocate-instance initialize make-instance make
+ no-next-method no-applicable-method no-method
+ change-class update-instance-for-different-class
+ shallow-clone deep-clone
+ class-redefinition
+ apply-generic apply-method apply-methods
+ compute-applicable-methods %compute-applicable-methods
+ method-more-specific? sort-applicable-methods
+ class-subclasses class-methods
+ goops-error
+ min-fixnum max-fixnum
+
+ instance?
+ slot-ref slot-set! slot-bound? slot-exists?
+ class-name class-direct-supers class-direct-subclasses
+ class-direct-methods class-direct-slots class-precedence-list
+ class-slots
+ generic-function-name
+ generic-function-methods method-generic-function
+ method-specializers method-formals
+ primitive-generic-generic enable-primitive-generic!
+ method-procedure accessor-method-slot-definition
+ make find-method get-keyword))
+
+
+;;;
+;;; Booting GOOPS is a tortuous process. We begin by loading a small
+;;; set of primitives from C.
+;;;
(eval-when (expand load eval)
- (use-modules ((language tree-il primitives) :select (add-interesting-primitive!)))
+ (load-extension (string-append "libguile-" (effective-version))
+ "scm_init_goops_builtins")
(add-interesting-primitive! 'class-of))
-;; Then load the rest of GOOPS
-(use-modules (oop goops dispatch))
+
+\f
+
+;;;
+;;; We then define the slots that must appear in all classes (<class>
+;;; objects) and slot definitions (<slot> objects). These slots must
+;;; appear in order. We'll use this list to statically compute offsets
+;;; for the various fields, to compute the struct layout for <class>
+;;; instances, and to compute the slot definition lists for <class>.
+;;; Because the list is needed at expansion-time, we define it as a
+;;; macro.
+;;;
+(define-syntax macro-fold-left
+ (syntax-rules ()
+ ((_ folder seed ()) seed)
+ ((_ folder seed (head . tail))
+ (macro-fold-left folder (folder head seed) tail))))
+
+(define-syntax macro-fold-right
+ (syntax-rules ()
+ ((_ folder seed ()) seed)
+ ((_ folder seed (head . tail))
+ (folder head (macro-fold-right folder seed tail)))))
+
+(define-syntax-rule (define-macro-folder macro-folder value ...)
+ (define-syntax macro-folder
+ (lambda (x)
+ (syntax-case x ()
+ ((_ fold visit seed)
+ ;; The datum->syntax makes it as if each `value' were present
+ ;; in the initial form, which allows them to be used as
+ ;; (components of) introduced identifiers.
+ #`(fold visit seed #,(datum->syntax #'visit '(value ...))))))))
+
+(define-macro-folder fold-class-slots
+ (layout #:class <protected-read-only-slot>)
+ (flags #:class <hidden-slot>)
+ (self #:class <self-slot>)
+ (instance-finalizer #:class <hidden-slot>)
+ (print)
+ (name #:class <protected-hidden-slot>)
+ (nfields #:class <hidden-slot>)
+ (%reserved #:class <hidden-slot>)
+ (redefined)
+ (direct-supers)
+ (direct-slots)
+ (direct-subclasses)
+ (direct-methods)
+ (cpl)
+ (slots))
+
+(define-macro-folder fold-slot-slots
+ (name #:init-keyword #:name)
+ (allocation #:init-keyword #:allocation #:init-value #:instance)
+ (init-keyword #:init-keyword #:init-keyword #:init-value #f)
+ (init-form #:init-keyword #:init-form)
+ (init-value #:init-keyword #:init-value)
+ (init-thunk #:init-keyword #:init-thunk #:init-value #f)
+ (options)
+ (getter #:init-keyword #:getter #:init-value #f)
+ (setter #:init-keyword #:setter #:init-value #f)
+ (accessor #:init-keyword #:accessor #:init-value #f)
+ ;; These last don't have #:init-keyword because they are meant to be
+ ;; set by `allocate-slots', not in compute-effective-slot-definition.
+ (slot-ref/raw #:init-value #f)
+ (slot-ref #:init-value #f)
+ (slot-set! #:init-value #f)
+ (index #:init-value #f)
+ (size #:init-value #f))
+
+;;;
+;;; Statically define variables for slot offsets: `class-index-layout'
+;;; will be 0, `class-index-flags' will be 1, and so on, and the same
+;;; for `slot-index-name' and such for <slot>.
+;;;
+(let-syntax ((define-slot-indexer
+ (syntax-rules ()
+ ((_ define-index prefix)
+ (define-syntax define-index
+ (lambda (x)
+ (define (id-append ctx a b)
+ (datum->syntax ctx (symbol-append (syntax->datum a)
+ (syntax->datum b))))
+ (define (tail-length tail)
+ (syntax-case tail ()
+ ((begin) 0)
+ ((visit head tail) (1+ (tail-length #'tail)))))
+ (syntax-case x ()
+ ((_ (name . _) tail)
+ #`(begin
+ (define-syntax #,(id-append #'name #'prefix #'name)
+ (identifier-syntax #,(tail-length #'tail)))
+ tail)))))))))
+ (define-slot-indexer define-class-index class-index-)
+ (define-slot-indexer define-slot-index slot-index-)
+ (fold-class-slots macro-fold-left define-class-index (begin))
+ (fold-slot-slots macro-fold-left define-slot-index (begin)))
+
+;;;
+;;; Structs that are vtables have a "flags" slot, which corresponds to
+;;; class-index-flags. `vtable-flag-vtable' indicates that instances of
+;;; a vtable are themselves vtables, and `vtable-flag-validated'
+;;; indicates that the struct's layout has been validated. goops.c
+;;; defines a few additional flags: one to indicate that a vtable is
+;;; actually a class, one to indicate that the class is "valid" (meaning
+;;; that it hasn't been redefined), and one to indicate that instances
+;;; of a class are slot definition objects (<slot> instances).
+;;;
+(define vtable-flag-goops-metaclass
+ (logior vtable-flag-vtable vtable-flag-goops-class))
+
+(define-inlinable (class-add-flags! class flags)
+ (struct-set! class class-index-flags
+ (logior flags (struct-ref class class-index-flags))))
+
+(define-inlinable (class-clear-flags! class flags)
+ (struct-set! class class-index-flags
+ (logand (lognot flags) (struct-ref class class-index-flags))))
+
+(define-inlinable (class-has-flags? class flags)
+ (eqv? flags
+ (logand (struct-ref class class-index-flags) flags)))
+
+(define-inlinable (class? obj)
+ (class-has-flags? (struct-vtable obj) vtable-flag-goops-metaclass))
+
+(define-inlinable (slot? obj)
+ (and (struct? obj)
+ (class-has-flags? (struct-vtable obj) vtable-flag-goops-slot)))
+
+(define-inlinable (instance? obj)
+ (class-has-flags? (struct-vtable obj) vtable-flag-goops-class))
+
+;;;
+;;; Now that we know the slots that must be present in classes, and
+;;; their offsets, we can create the root of the class hierarchy.
+;;;
+;;; Note that the `direct-supers', `direct-slots', `cpl', and `slots'
+;;; fields will be updated later, once we can create slot definition
+;;; objects and once we have definitions for <top> and <object>.
+;;;
+(define <class>
+ (let-syntax ((cons-layout
+ ;; A simple way to compute class layout for the concrete
+ ;; types used in <class>.
+ (syntax-rules (<protected-read-only-slot>
+ <self-slot>
+ <hidden-slot>
+ <protected-hidden-slot>)
+ ((_ (name) tail)
+ (string-append "pw" tail))
+ ((_ (name #:class <protected-read-only-slot>) tail)
+ (string-append "pr" tail))
+ ((_ (name #:class <self-slot>) tail)
+ (string-append "sr" tail))
+ ((_ (name #:class <hidden-slot>) tail)
+ (string-append "uh" tail))
+ ((_ (name #:class <protected-hidden-slot>) tail)
+ (string-append "ph" tail)))))
+ (let* ((layout (fold-class-slots macro-fold-right cons-layout ""))
+ (nfields (/ (string-length layout) 2))
+ (<class> (%make-vtable-vtable layout)))
+ (class-add-flags! <class> (logior vtable-flag-goops-class
+ vtable-flag-goops-valid))
+ (struct-set! <class> class-index-name '<class>)
+ (struct-set! <class> class-index-nfields nfields)
+ (struct-set! <class> class-index-direct-supers '())
+ (struct-set! <class> class-index-direct-slots '())
+ (struct-set! <class> class-index-direct-subclasses '())
+ (struct-set! <class> class-index-direct-methods '())
+ (struct-set! <class> class-index-cpl '())
+ (struct-set! <class> class-index-slots '())
+ (struct-set! <class> class-index-redefined #f)
+ <class>)))
+
+;;;
+;;; Accessors to fields of <class>.
+;;;
+(define-syntax-rule (define-class-accessor name docstring field)
+ (define (name obj)
+ docstring
+ (let ((val obj))
+ (unless (class? val)
+ (scm-error 'wrong-type-arg #f "Not a class: ~S"
+ (list val) #f))
+ (struct-ref val field))))
+
+(define-class-accessor class-name
+ "Return the class name of @var{obj}."
+ class-index-name)
+(define-class-accessor class-direct-supers
+ "Return the direct superclasses of the class @var{obj}."
+ class-index-direct-supers)
+(define-class-accessor class-direct-slots
+ "Return the direct slots of the class @var{obj}."
+ class-index-direct-slots)
+(define-class-accessor class-direct-subclasses
+ "Return the direct subclasses of the class @var{obj}."
+ class-index-direct-subclasses)
+(define-class-accessor class-direct-methods
+ "Return the direct methods of the class @var{obj}."
+ class-index-direct-methods)
+(define-class-accessor class-precedence-list
+ "Return the class precedence list of the class @var{obj}."
+ class-index-cpl)
+(define-class-accessor class-slots
+ "Return the slot list of the class @var{obj}."
+ class-index-slots)
+
+(define (class-subclasses c)
+ "Compute a list of all subclasses of @var{c}, direct and indirect."
+ (define (all-subclasses c)
+ (cons c (append-map all-subclasses
+ (class-direct-subclasses c))))
+ (delete-duplicates (cdr (all-subclasses c)) eq?))
+
+(define (class-methods c)
+ "Compute a list of all methods that specialize on @var{c} or
+subclasses of @var{c}."
+ (delete-duplicates (append-map class-direct-methods
+ (cons c (class-subclasses c)))
+ eq?))
+
+(define (is-a? obj class)
+ "Return @code{#t} if @var{obj} is an instance of @var{class}, or
+@code{#f} otherwise."
+ (and (memq class (class-precedence-list (class-of obj))) #t))
+
+
+\f
+
+;;;
+;;; At this point, <class> is missing slot definitions, but we can't
+;;; create slot definitions until we have a slot definition class.
+;;; Continue with manual object creation until we're able to bootstrap
+;;; more of the protocol. Again, the CPL and class hierarchy slots
+;;; remain uninitialized.
+;;;
+(define* (get-keyword key l #:optional default)
+ "Determine an associated value for the keyword @var{key} from the list
+@var{l}. The list @var{l} has to consist of an even number of elements,
+where, starting with the first, every second element is a keyword,
+followed by its associated value. If @var{l} does not hold a value for
+@var{key}, the value @var{default} is returned."
+ (unless (keyword? key)
+ (scm-error 'wrong-type-arg #f "Not a keyword: ~S" (list key) #f))
+ (let lp ((l l))
+ (match l
+ (() default)
+ ((kw arg . l)
+ (unless (keyword? kw)
+ (scm-error 'wrong-type-arg #f "Not a keyword: ~S" (list kw) #f))
+ (if (eq? kw key) arg (lp l))))))
+
+(define *unbound* (list 'unbound))
+
+(define-inlinable (unbound? x)
+ (eq? x *unbound*))
+
+(define (%allocate-instance class)
+ (let ((obj (allocate-struct class (struct-ref class class-index-nfields))))
+ (%clear-fields! obj *unbound*)
+ obj))
+
+(define <slot>
+ (let-syntax ((cons-layout
+ ;; All slots are "pw" in <slot>.
+ (syntax-rules ()
+ ((_ _ tail) (string-append "pw" tail)))))
+ (let* ((layout (fold-slot-slots macro-fold-right cons-layout ""))
+ (nfields (/ (string-length layout) 2))
+ (<slot> (make-struct/no-tail <class> (make-struct-layout layout))))
+ (class-add-flags! <slot> (logior vtable-flag-goops-class
+ vtable-flag-goops-slot
+ vtable-flag-goops-valid))
+ (struct-set! <slot> class-index-name '<slot>)
+ (struct-set! <slot> class-index-nfields nfields)
+ (struct-set! <slot> class-index-direct-supers '())
+ (struct-set! <slot> class-index-direct-slots '())
+ (struct-set! <slot> class-index-direct-subclasses '())
+ (struct-set! <slot> class-index-direct-methods '())
+ (struct-set! <slot> class-index-cpl (list <slot>))
+ (struct-set! <slot> class-index-slots '())
+ (struct-set! <slot> class-index-redefined #f)
+ <slot>)))
+
+;;; Access to slot objects is performance-sensitive for slot-ref, so in
+;;; addition to the type-checking accessors that we export, we also
+;;; define some internal inlined helpers that just do an unchecked
+;;; struct-ref in cases where we know the object must be a slot, as
+;;; when accessing class-slots.
+;;;
+(define-syntax-rule (define-slot-accessor name docstring %name field)
+ (begin
+ (define-syntax-rule (%name obj)
+ (struct-ref obj field))
+ (define (name obj)
+ docstring
+ (unless (slot? obj)
+ (scm-error 'wrong-type-arg #f "Not a slot: ~S"
+ (list obj) #f))
+ (%name obj))))
+
+(define-slot-accessor slot-definition-name
+ "Return the name of @var{obj}."
+ %slot-definition-name slot-index-name)
+(define-slot-accessor slot-definition-allocation
+ "Return the allocation of the slot @var{obj}."
+ %slot-definition-allocation slot-index-allocation)
+(define-slot-accessor slot-definition-init-keyword
+ "Return the init keyword of the slot @var{obj}, or @code{#f}."
+ %slot-definition-init-keyword slot-index-init-keyword)
+(define-slot-accessor slot-definition-init-form
+ "Return the init form of the slot @var{obj}, or the unbound value"
+ %slot-definition-init-form slot-index-init-form)
+(define-slot-accessor slot-definition-init-value
+ "Return the init value of the slot @var{obj}, or the unbound value."
+ %slot-definition-init-value slot-index-init-value)
+(define-slot-accessor slot-definition-init-thunk
+ "Return the init thunk of the slot @var{obj}, or @code{#f}."
+ %slot-definition-init-thunk slot-index-init-thunk)
+(define-slot-accessor slot-definition-options
+ "Return the initargs given when creating the slot @var{obj}."
+ %slot-definition-options slot-index-options)
+(define-slot-accessor slot-definition-getter
+ "Return the getter of the slot @var{obj}, or @code{#f}."
+ %slot-definition-getter slot-index-getter)
+(define-slot-accessor slot-definition-setter
+ "Return the setter of the slot @var{obj}, or @code{#f}."
+ %slot-definition-setter slot-index-setter)
+(define-slot-accessor slot-definition-accessor
+ "Return the accessor of the slot @var{obj}, or @code{#f}."
+ %slot-definition-accessor slot-index-accessor)
+(define-slot-accessor slot-definition-slot-ref/raw
+ "Return the raw slot-ref procedure of the slot @var{obj}."
+ %slot-definition-slot-ref/raw slot-index-slot-ref/raw)
+(define-slot-accessor slot-definition-slot-ref
+ "Return the slot-ref procedure of the slot @var{obj}."
+ %slot-definition-slot-ref slot-index-slot-ref)
+(define-slot-accessor slot-definition-slot-set!
+ "Return the slot-set! procedure of the slot @var{obj}."
+ %slot-definition-slot-set! slot-index-slot-set!)
+(define-slot-accessor slot-definition-index
+ "Return the allocated struct offset of the slot @var{obj}, or @code{#f}."
+ %slot-definition-index slot-index-index)
+(define-slot-accessor slot-definition-size
+ "Return the number fields used by the slot @var{obj}, or @code{#f}."
+ %slot-definition-size slot-index-size)
+
+;; Boot definition.
+(define (direct-slot-definition-class class initargs)
+ (get-keyword #:class initargs <slot>))
+
+;; Boot definition.
+(define (make-slot class initargs)
+ (let ((slot (make-struct/no-tail class)))
+ (define-syntax-rule (init-slot offset kw default)
+ (struct-set! slot offset (get-keyword kw initargs default)))
+ (init-slot slot-index-name #:name #f)
+ (init-slot slot-index-allocation #:allocation #:instance)
+ (init-slot slot-index-init-keyword #:init-keyword #f)
+ (init-slot slot-index-init-form #:init-form *unbound*)
+ (init-slot slot-index-init-value #:init-value *unbound*)
+ (struct-set! slot slot-index-init-thunk
+ (or (get-keyword #:init-thunk initargs #f)
+ (let ((val (%slot-definition-init-value slot)))
+ (if (unbound? val)
+ #f
+ (lambda () val)))))
+ (struct-set! slot slot-index-options initargs)
+ (init-slot slot-index-getter #:getter #f)
+ (init-slot slot-index-setter #:setter #f)
+ (init-slot slot-index-accessor #:accessor #f)
+ (struct-set! slot slot-index-slot-ref/raw #f)
+ (struct-set! slot slot-index-slot-ref #f)
+ (struct-set! slot slot-index-slot-set! #f)
+ (struct-set! slot slot-index-index #f)
+ (struct-set! slot slot-index-size #f)
+ slot))
+
+;; Boot definition.
+(define (make class . args)
+ (unless (memq <slot> (class-precedence-list class))
+ (error "Unsupported class: ~S" class))
+ (make-slot class args))
+
+;; Boot definition.
+(define (compute-direct-slot-definition class initargs)
+ (apply make (direct-slot-definition-class class initargs) initargs))
+
+(define (compute-direct-slot-definition-initargs class slot-spec)
+ (match slot-spec
+ ((? symbol? name) (list #:name name))
+ (((? symbol? name) . initargs)
+ (cons* #:name name
+ ;; If there is an #:init-form, the `class' macro will have
+ ;; already added an #:init-thunk. Still, if there isn't an
+ ;; #:init-thunk already but we do have an #:init-value,
+ ;; synthesize an #:init-thunk initarg. This will ensure
+ ;; that the #:init-thunk gets passed on to the effective
+ ;; slot definition too.
+ (if (get-keyword #:init-thunk initargs)
+ initargs
+ (let ((value (get-keyword #:init-value initargs *unbound*)))
+ (if (unbound? value)
+ initargs
+ (cons* #:init-thunk (lambda () value) initargs))))))))
+
+(let ()
+ (define-syntax cons-slot
+ (syntax-rules ()
+ ((_ (name #:class class) tail)
+ ;; Special case to avoid referencing specialized <slot> kinds,
+ ;; which are not defined yet.
+ (cons (list 'name) tail))
+ ((_ (name . initargs) tail)
+ (cons (list 'name . initargs) tail))))
+ (define-syntax-rule (initialize-direct-slots! class fold-slots)
+ (let ((specs (fold-slots macro-fold-right cons-slot '())))
+ (define (make-direct-slot-definition spec)
+ (let ((initargs (compute-direct-slot-definition-initargs class spec)))
+ (compute-direct-slot-definition class initargs)))
+ (struct-set! class class-index-direct-slots
+ (map make-direct-slot-definition specs))))
+
+ (initialize-direct-slots! <class> fold-class-slots)
+ (initialize-direct-slots! <slot> fold-slot-slots))
+
+
+\f
+
+;;;
+;;; OK, at this point we have initialized `direct-slots' on both <class>
+;;; and <slot>. We need to define a standard way to make subclasses:
+;;; how to compute the precedence list of subclasses, how to compute the
+;;; list of slots in a subclass, and what layout to use for instances of
+;;; those classes.
+;;;
+(define (compute-std-cpl c get-direct-supers)
+ "The standard class precedence list computation algorithm."
+ (define (only-non-null lst)
+ (filter (lambda (l) (not (null? l))) lst))
+
+ (define (merge-lists reversed-partial-result inputs)
+ (cond
+ ((every null? inputs)
+ (reverse! reversed-partial-result))
+ (else
+ (let* ((candidate (lambda (c)
+ (and (not (any (lambda (l)
+ (memq c (cdr l)))
+ inputs))
+ c)))
+ (candidate-car (lambda (l)
+ (and (not (null? l))
+ (candidate (car l)))))
+ (next (any candidate-car inputs)))
+ (unless next
+ (goops-error "merge-lists: Inconsistent precedence graph"))
+ (let ((remove-next (lambda (l)
+ (if (eq? (car l) next)
+ (cdr l)
+ l))))
+ (merge-lists (cons next reversed-partial-result)
+ (only-non-null (map remove-next inputs))))))))
+ (let ((c-direct-supers (get-direct-supers c)))
+ (merge-lists (list c)
+ (only-non-null (append (map class-precedence-list
+ c-direct-supers)
+ (list c-direct-supers))))))
+
+;; This version of compute-cpl is replaced with a generic function once
+;; GOOPS has booted.
+(define (compute-cpl class)
+ (compute-std-cpl class class-direct-supers))
+
+(define (effective-slot-definition-class class slot)
+ (class-of slot))
+
+(define (compute-effective-slot-definition class slot)
+ ;; FIXME: Support slot being a list of slots, as in CLOS.
+ (apply make
+ (effective-slot-definition-class class slot)
+ (slot-definition-options slot)))
+
+(define (build-slots-list dslots cpl)
+ (define (slot-memq slot slots)
+ (let ((name (%slot-definition-name slot)))
+ (let lp ((slots slots))
+ (match slots
+ (() #f)
+ ((slot . slots)
+ (or (eq? (%slot-definition-name slot) name) (lp slots)))))))
+ (define (check-cpl slots static-slots)
+ (when (or-map (lambda (slot) (slot-memq slot slots)) static-slots)
+ (scm-error 'misc-error #f
+ "a predefined static inherited field cannot be redefined"
+ '() '())))
+ (define (remove-duplicate-slots slots)
+ (let lp ((slots (reverse slots)) (res '()) (seen '()))
+ (match slots
+ (() res)
+ ((slot . slots)
+ (let ((name (%slot-definition-name slot)))
+ (if (memq name seen)
+ (lp slots res seen)
+ (lp slots (cons slot res) (cons name seen))))))))
+ ;; For subclases of <class> and <slot>, we need to ensure that the
+ ;; <class> or <slot> slots come first.
+ (let* ((static-slots (cond
+ ((memq <class> cpl)
+ (when (memq <slot> cpl) (error "invalid class"))
+ (struct-ref <class> class-index-slots))
+ ((memq <slot> cpl)
+ (struct-ref <slot> class-index-slots))
+ (else #f))))
+ (when static-slots
+ (check-cpl dslots static-slots))
+ (let lp ((cpl (cdr cpl)) (res dslots) (static-slots '()))
+ (match cpl
+ (() (remove-duplicate-slots (append static-slots res)))
+ ((head . cpl)
+ (let ((new-slots (struct-ref head class-index-direct-slots)))
+ (cond
+ ((not static-slots)
+ (lp cpl (append new-slots res) static-slots))
+ ((or (eq? head <class>) (eq? head <slot>))
+ ;; Move static slots to the head of the list.
+ (lp cpl res new-slots))
+ (else
+ (check-cpl new-slots static-slots)
+ (lp cpl (append new-slots res) static-slots)))))))))
+
+;; Boot definition.
+(define (compute-get-n-set class slot)
+ (let ((index (struct-ref class class-index-nfields)))
+ (struct-set! class class-index-nfields (1+ index))
+ index))
+
+;;; Pre-generate getters and setters for the first 20 slots.
+(define-syntax define-standard-accessor-method
+ (lambda (stx)
+ (define num-standard-pre-cache 20)
+ (syntax-case stx ()
+ ((_ ((proc n) arg ...) body)
+ #`(define proc
+ (let ((cache (vector #,@(map (lambda (n*)
+ #`(lambda (arg ...)
+ (let ((n #,n*))
+ body)))
+ (iota num-standard-pre-cache)))))
+ (lambda (n)
+ (if (< n #,num-standard-pre-cache)
+ (vector-ref cache n)
+ (lambda (arg ...) body)))))))))
+
+(define-standard-accessor-method ((bound-check-get n) o)
+ (let ((x (struct-ref o n)))
+ (if (unbound? x)
+ (slot-unbound o)
+ x)))
+
+(define-standard-accessor-method ((standard-get n) o)
+ (struct-ref o n))
+
+(define-standard-accessor-method ((standard-set n) o v)
+ (struct-set! o n v))
+
+(define (allocate-slots class slots)
+ "Transform the computed list of direct slot definitions @var{slots}
+into a corresponding list of effective slot definitions, allocating
+slots as we go."
+ (define (make-effective-slot-definition slot)
+ ;; `compute-get-n-set' is expected to mutate `nfields' if it
+ ;; allocates a field to the object. Pretty strange, but we preserve
+ ;; the behavior for backward compatibility.
+ (let* ((slot (compute-effective-slot-definition class slot))
+ (name (%slot-definition-name slot))
+ (index (struct-ref class class-index-nfields))
+ (g-n-s (compute-get-n-set class slot))
+ (size (- (struct-ref class class-index-nfields) index)))
+ (call-with-values
+ (lambda ()
+ (match g-n-s
+ ((? integer?)
+ (unless (= size 1)
+ (error "unexpected return from compute-get-n-set"))
+ (values (standard-get g-n-s)
+ (if (slot-definition-init-thunk slot)
+ (standard-get g-n-s)
+ (bound-check-get g-n-s))
+ (standard-set g-n-s)))
+ (((? procedure? get) (? procedure? set))
+ (values get
+ (lambda (o)
+ (let ((value (get o)))
+ (if (unbound? value)
+ (slot-unbound class o name)
+ value)))
+ set))))
+ (lambda (get/raw get set)
+ (struct-set! slot slot-index-slot-ref/raw get/raw)
+ (struct-set! slot slot-index-slot-ref get)
+ (struct-set! slot slot-index-slot-set! set)
+ (struct-set! slot slot-index-index index)
+ (struct-set! slot slot-index-size size)))
+ slot))
+ (struct-set! class class-index-nfields 0)
+ (map-in-order make-effective-slot-definition slots))
+
+(define (%compute-layout slots nfields is-class?)
+ (define (slot-protection-and-kind slot)
+ (define (subclass? class parent)
+ (memq parent (class-precedence-list class)))
+ (let ((type (kw-arg-ref (%slot-definition-options slot) #:class)))
+ (if (and type (subclass? type <foreign-slot>))
+ (values (cond
+ ((subclass? type <self-slot>) #\s)
+ ((subclass? type <protected-slot>) #\p)
+ (else #\u))
+ (cond
+ ((subclass? type <opaque-slot>) #\o)
+ ((subclass? type <read-only-slot>) #\r)
+ ((subclass? type <hidden-slot>) #\h)
+ (else #\w)))
+ (values #\p #\w))))
+ (let ((layout (make-string (* nfields 2))))
+ (let lp ((n 0) (slots slots))
+ (match slots
+ (()
+ (unless (= n nfields) (error "bad nfields"))
+ (when is-class?
+ (let ((class-layout (struct-ref <class> class-index-layout)))
+ (unless (string-prefix? (symbol->string class-layout) layout)
+ (error "bad layout for class"))))
+ layout)
+ ((slot . slots)
+ (unless (= n (%slot-definition-index slot)) (error "bad allocation"))
+ (call-with-values (lambda () (slot-protection-and-kind slot))
+ (lambda (protection kind)
+ (let init ((n n) (size (%slot-definition-size slot)))
+ (cond
+ ((zero? size) (lp n slots))
+ (else
+ (unless (< n nfields) (error "bad nfields"))
+ (string-set! layout (* n 2) protection)
+ (string-set! layout (1+ (* n 2)) kind)
+ (init (1+ n) (1- size))))))))))))
+
+
+\f
+
+;;;
+;;; With all of this, we are now able to define subclasses of <class>.
+;;;
+(define (%prep-layout! class)
+ (let* ((is-class? (and (memq <class> (struct-ref class class-index-cpl)) #t))
+ (layout (%compute-layout (struct-ref class class-index-slots)
+ (struct-ref class class-index-nfields)
+ is-class?)))
+ (%init-layout! class layout)))
+
+(define (make-standard-class class name dsupers dslots)
+ (let ((z (make-struct/no-tail class)))
+ (define (make-direct-slot-definition dslot)
+ (let ((initargs (compute-direct-slot-definition-initargs z dslot)))
+ (compute-direct-slot-definition z initargs)))
+
+ (struct-set! z class-index-name name)
+ (struct-set! z class-index-nfields 0)
+ (struct-set! z class-index-direct-supers dsupers)
+ (struct-set! z class-index-direct-subclasses '())
+ (struct-set! z class-index-direct-methods '())
+ (struct-set! z class-index-redefined #f)
+ (let ((cpl (compute-cpl z)))
+ (struct-set! z class-index-cpl cpl)
+ (when (memq <slot> cpl)
+ (class-add-flags! z vtable-flag-goops-slot))
+ (let* ((dslots (map make-direct-slot-definition dslots))
+ (slots (allocate-slots z (build-slots-list dslots cpl))))
+ (struct-set! z class-index-direct-slots dslots)
+ (struct-set! z class-index-slots slots)))
+ (for-each
+ (lambda (super)
+ (let ((subclasses (struct-ref super class-index-direct-subclasses)))
+ (struct-set! super class-index-direct-subclasses
+ (cons z subclasses))))
+ dsupers)
+ (%prep-layout! z)
+ z))
+
+(define-syntax define-standard-class
+ (syntax-rules ()
+ ((define-standard-class name (super ...) #:metaclass meta slot ...)
+ (define name
+ (make-standard-class meta 'name (list super ...) '(slot ...))))
+ ((define-standard-class name (super ...) slot ...)
+ (define-standard-class name (super ...) #:metaclass <class> slot ...))))
+
+
+\f
+
+;;;
+;;; Sweet! Now we can define <top> and <object>, and finish
+;;; initializing the `direct-subclasses', `direct-supers', and `cpl'
+;;; slots of <class>.
+;;;
+(define-standard-class <top> ())
+(define-standard-class <object> (<top>))
+
+;; The inheritance links for <top>, <object>, <class>, and <slot> were
+;; partially initialized. Correct them here.
+(struct-set! <object> class-index-direct-subclasses (list <slot> <class>))
+(struct-set! <class> class-index-direct-supers (list <object>))
+(struct-set! <slot> class-index-direct-supers (list <object>))
+(struct-set! <class> class-index-cpl (list <class> <object> <top>))
+(struct-set! <slot> class-index-cpl (list <slot> <object> <top>))
+
+
+\f
+
+;;;
+;;; We can also define the various slot types, and finish initializing
+;;; `direct-slots' and `slots' on <class> and <slot>.
+;;;
+(define-standard-class <foreign-slot> (<slot>))
+(define-standard-class <protected-slot> (<foreign-slot>))
+(define-standard-class <hidden-slot> (<foreign-slot>))
+(define-standard-class <opaque-slot> (<foreign-slot>))
+(define-standard-class <read-only-slot> (<foreign-slot>))
+(define-standard-class <self-slot> (<read-only-slot>))
+(define-standard-class <protected-opaque-slot> (<protected-slot>
+ <opaque-slot>))
+(define-standard-class <protected-hidden-slot> (<protected-slot>
+ <hidden-slot>))
+(define-standard-class <protected-read-only-slot> (<protected-slot>
+ <read-only-slot>))
+(define-standard-class <scm-slot> (<protected-slot>))
+(define-standard-class <int-slot> (<foreign-slot>))
+(define-standard-class <float-slot> (<foreign-slot>))
+(define-standard-class <double-slot> (<foreign-slot>))
+
+
+\f
;;;
-;;; Compiling next methods into method bodies
+;;; Finally! Initialize `direct-slots' and `slots' on <class>, and
+;;; `slots' on <slot>.
+;;;
+(let ()
+ (define-syntax-rule (cons-slot (name . initargs) tail)
+ (cons (list 'name . initargs) tail))
+ (define-syntax-rule (initialize-direct-slots! class fold-slots)
+ (let ((specs (fold-slots macro-fold-right cons-slot '())))
+ (define (make-direct-slot-definition spec)
+ (let ((initargs (compute-direct-slot-definition-initargs class spec)))
+ (compute-direct-slot-definition class initargs)))
+ (struct-set! class class-index-direct-slots
+ (map make-direct-slot-definition specs))))
+ (define (initialize-slots! class)
+ (let ((slots (build-slots-list (class-direct-slots class)
+ (class-precedence-list class))))
+ (struct-set! class class-index-slots (allocate-slots class slots))))
+
+ ;; Finish initializing <class> with the specialized slot kinds.
+ (initialize-direct-slots! <class> fold-class-slots)
+
+ (initialize-slots! <class>)
+ (initialize-slots! <slot>))
+
+
+\f
+
;;;
+;;; Now, to build out the class hierarchy.
+;;;
+
+(define-standard-class <procedure-class> (<class>))
+
+(define-standard-class <applicable-struct-class>
+ (<procedure-class>))
+(class-add-flags! <applicable-struct-class>
+ vtable-flag-applicable-vtable)
+
+(define-standard-class <applicable-struct-with-setter-class>
+ (<applicable-struct-class>))
+(class-add-flags! <applicable-struct-with-setter-class>
+ vtable-flag-setter-vtable)
+
+(define-standard-class <applicable> (<top>))
+(define-standard-class <applicable-struct> (<object> <applicable>)
+ #:metaclass <applicable-struct-class>
+ procedure)
+(define-standard-class <applicable-struct-with-setter> (<applicable-struct>)
+ #:metaclass <applicable-struct-with-setter-class>
+ setter)
+(define-standard-class <generic> (<applicable-struct>)
+ #:metaclass <applicable-struct-class>
+ methods
+ (n-specialized #:init-value 0)
+ (extended-by #:init-value ())
+ effective-methods)
+(define-standard-class <extended-generic> (<generic>)
+ #:metaclass <applicable-struct-class>
+ (extends #:init-value ()))
+(define-standard-class <generic-with-setter> (<generic>
+ <applicable-struct-with-setter>)
+ #:metaclass <applicable-struct-with-setter-class>)
+(define-standard-class <accessor> (<generic-with-setter>)
+ #:metaclass <applicable-struct-with-setter-class>)
+(define-standard-class <extended-generic-with-setter> (<extended-generic>
+ <generic-with-setter>)
+ #:metaclass <applicable-struct-with-setter-class>)
+(define-standard-class <extended-accessor> (<accessor>
+ <extended-generic-with-setter>)
+ #:metaclass <applicable-struct-with-setter-class>)
+
+(define-standard-class <method> (<object>)
+ generic-function
+ specializers
+ procedure
+ formals
+ body
+ make-procedure)
+(define-standard-class <accessor-method> (<method>)
+ (slot-definition #:init-keyword #:slot-definition))
+
+(define-standard-class <boolean> (<top>))
+(define-standard-class <char> (<top>))
+(define-standard-class <list> (<top>))
+;; Not all pairs are lists, but there is code out there that relies on
+;; (is-a? '(1 2 3) <list>) to work. Terrible. How to fix?
+(define-standard-class <pair> (<list>))
+(define-standard-class <null> (<list>))
+(define-standard-class <string> (<top>))
+(define-standard-class <symbol> (<top>))
+(define-standard-class <vector> (<top>))
+(define-standard-class <foreign> (<top>))
+(define-standard-class <hashtable> (<top>))
+(define-standard-class <fluid> (<top>))
+(define-standard-class <dynamic-state> (<top>))
+(define-standard-class <frame> (<top>))
+(define-standard-class <vm-continuation> (<top>))
+(define-standard-class <bytevector> (<top>))
+(define-standard-class <uvec> (<bytevector>))
+(define-standard-class <array> (<top>))
+(define-standard-class <bitvector> (<top>))
+(define-standard-class <number> (<top>))
+(define-standard-class <complex> (<number>))
+(define-standard-class <real> (<complex>))
+(define-standard-class <integer> (<real>))
+(define-standard-class <fraction> (<real>))
+(define-standard-class <keyword> (<top>))
+(define-standard-class <unknown> (<top>))
+(define-standard-class <procedure> (<applicable>)
+ #:metaclass <procedure-class>)
+(define-standard-class <primitive-generic> (<procedure>)
+ #:metaclass <procedure-class>)
+(define-standard-class <port> (<top>))
+(define-standard-class <input-port> (<port>))
+(define-standard-class <output-port> (<port>))
+(define-standard-class <input-output-port> (<input-port> <output-port>))
+
+(define (inherit-applicable! class)
+ "An internal routine to redefine a SMOB class that was added after
+GOOPS was loaded, and on which scm_set_smob_apply installed an apply
+function."
+ ;; Why not use class-redefinition? We would, except that loading the
+ ;; compiler to compile effective methods can happen while GOOPS has
+ ;; only been partially loaded, and loading the compiler might cause
+ ;; SMOB types to be defined that need this facility. Instead we make
+ ;; a very specific hack, not a general solution. Probably the right
+ ;; solution is to avoid using the compiler, but that is another kettle
+ ;; of fish.
+ (unless (memq <applicable> (class-precedence-list class))
+ (unless (null? (class-slots class))
+ (error "SMOB object has slots?"))
+ (for-each
+ (lambda (super)
+ (let ((subclasses (struct-ref super class-index-direct-subclasses)))
+ (struct-set! super class-index-direct-subclasses
+ (delq class subclasses))))
+ (struct-ref class class-index-direct-supers))
+ (struct-set! class class-index-direct-supers (list <applicable>))
+ (struct-set! class class-index-cpl (compute-cpl class))
+ (let ((subclasses (struct-ref <applicable> class-index-direct-subclasses)))
+ (struct-set! <applicable> class-index-direct-subclasses
+ (cons class subclasses)))))
-;;; 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.
+
+\f
+
+;;;
+;;; At this point we have defined the class hierarchy, and it's time to
+;;; move on to instance allocation and generics. Once we have generics,
+;;; we'll fill out the metaobject protocol.
;;;
-;;; 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.
+;;; Here we define a limited version of `make', so that we can allocate
+;;; instances of specific classes. This definition will be replaced
+;;; later.
;;;
-;;; I think this whole generic application mess would benefit from a
-;;; strict MOP.
+(define (%invalidate-method-cache! gf)
+ (slot-set! gf 'effective-methods '())
+ (recompute-generic-function-dispatch-procedure! gf))
+
+;; Boot definition.
+(define (invalidate-method-cache! gf)
+ (%invalidate-method-cache! gf))
-(define (compute-cmethod methods types)
+(define (make class . args)
+ (cond
+ ((or (eq? class <generic>) (eq? class <accessor>))
+ (let ((z (make-struct/no-tail class #f '() 0 '())))
+ (set-procedure-property! z 'name (get-keyword #:name args #f))
+ (invalidate-method-cache! z)
+ (when (eq? class <accessor>)
+ (let ((setter (get-keyword #:setter args #f)))
+ (when setter
+ (slot-set! z 'setter setter))))
+ z))
+ (else
+ (let ((z (%allocate-instance class)))
+ (cond
+ ((or (eq? class <method>) (eq? class <accessor-method>))
+ (for-each (match-lambda
+ ((kw slot default)
+ (slot-set! z slot (get-keyword kw args default))))
+ '((#:generic-function generic-function #f)
+ (#:specializers specializers ())
+ (#:procedure procedure #f)
+ (#:formals formals ())
+ (#:body body ())
+ (#:make-procedure make-procedure #f))))
+ ((memq <class> (class-precedence-list class))
+ (class-add-flags! z (logior vtable-flag-goops-class
+ vtable-flag-goops-valid))
+ (for-each (match-lambda
+ ((kw slot default)
+ (slot-set! z slot (get-keyword kw args default))))
+ '((#:name name ???)
+ (#:dsupers direct-supers ())
+ (#:slots direct-slots ()))))
+ (else
+ (error "boot `make' does not support this class" class)))
+ z))))
+
+
+\f
+
+;;;
+;;; Slot access.
+;;;
+;;; Before we go on, some notes about class redefinition. In GOOPS,
+;;; classes can be redefined. Redefinition of a class marks the class
+;;; as invalid, and instances will be lazily migrated over to the new
+;;; representation as they are accessed. Migration happens when
+;;; `class-of' is called on an instance. For more technical details on
+;;; object redefinition, see struct.h.
+;;;
+;;; In the following interfaces, class-of handles the redefinition
+;;; protocol. I would think though that there is some thread-unsafety
+;;; here though as the { class, object data } pair needs to be accessed
+;;; atomically, not the { class, object } pair.
+;;;
+(define-inlinable (%class-slot-definition class slot-name kt kf)
+ (let lp ((slots (struct-ref class class-index-slots)))
+ (match slots
+ ((slot . slots)
+ (if (eq? (%slot-definition-name slot) slot-name)
+ (kt slot)
+ (lp slots)))
+ (_ (kf)))))
+
+(define (class-slot-definition class slot-name)
+ (unless (class? class)
+ (scm-error 'wrong-type-arg #f "Not a class: ~S" (list class) #f))
+ (%class-slot-definition class slot-name
+ (lambda (slot) slot)
+ (lambda () #f)))
+
+(define (slot-ref obj slot-name)
+ "Return the value from @var{obj}'s slot with the nam var{slot_name}."
+ (let ((class (class-of obj)))
+ (define (have-slot slot)
+ ((%slot-definition-slot-ref slot) obj))
+ (define (no-slot)
+ (unless (symbol? slot-name)
+ (scm-error 'wrong-type-arg #f "Not a symbol: ~S"
+ (list slot-name) #f))
+ (let ((val (slot-missing class obj slot-name)))
+ (if (unbound? val)
+ (slot-unbound class obj slot-name)
+ val)))
+ (%class-slot-definition class slot-name have-slot no-slot)))
+
+(define (slot-set! obj slot-name value)
+ "Set the slot named @var{slot_name} of @var{obj} to @var{value}."
+ (let ((class (class-of obj)))
+ (define (have-slot slot)
+ ((%slot-definition-slot-set! slot) obj value))
+ (define (no-slot)
+ (unless (symbol? slot-name)
+ (scm-error 'wrong-type-arg #f "Not a symbol: ~S"
+ (list slot-name) #f))
+ (slot-missing class obj slot-name value))
+
+ (%class-slot-definition class slot-name have-slot no-slot)))
+
+(define (slot-bound? obj slot-name)
+ "Return the value from @var{obj}'s slot with the nam var{slot_name}."
+ (let ((class (class-of obj)))
+ (define (have-slot slot)
+ (not (unbound? ((%slot-definition-slot-ref/raw slot) obj))))
+ (define (no-slot)
+ (unless (symbol? slot-name)
+ (scm-error 'wrong-type-arg #f "Not a symbol: ~S"
+ (list slot-name) #f))
+ (not (unbound? (slot-missing class obj slot-name))))
+ (%class-slot-definition class slot-name have-slot no-slot)))
+
+(define (slot-exists? obj slot-name)
+ "Return @code{#t} if @var{obj} has a slot named @var{slot_name}."
+ (define (have-slot slot) #t)
+ (define (no-slot)
+ (unless (symbol? slot-name)
+ (scm-error 'wrong-type-arg #f "Not a symbol: ~S"
+ (list slot-name) #f))
+ #f)
+ (%class-slot-definition (class-of obj) slot-name have-slot no-slot))
+
+(begin-deprecated
+ (define (check-slot-args class obj slot-name)
+ (unless (eq? class (class-of obj))
+ (scm-error 'wrong-type-arg #f "~S is not the class of ~S"
+ (list class obj) #f))
+ (unless (symbol? slot-name)
+ (scm-error 'wrong-type-arg #f "Not a symbol: ~S"
+ (list slot-name) #f)))
+
+ (define (slot-ref-using-class class obj slot-name)
+ (issue-deprecation-warning "slot-ref-using-class is deprecated. "
+ "Use slot-ref instead.")
+ (check-slot-args class obj slot-name)
+ (slot-ref obj slot-name))
+
+ (define (slot-set-using-class! class obj slot-name value)
+ (issue-deprecation-warning "slot-set-using-class! is deprecated. "
+ "Use slot-set! instead.")
+ (check-slot-args class obj slot-name)
+ (slot-set! obj slot-name value))
+
+ (define (slot-bound-using-class? class obj slot-name)
+ (issue-deprecation-warning "slot-bound-using-class? is deprecated. "
+ "Use slot-bound? instead.")
+ (check-slot-args class obj slot-name)
+ (slot-bound? obj slot-name))
+
+ (define (slot-exists-using-class? class obj slot-name)
+ (issue-deprecation-warning "slot-exists-using-class? is deprecated. "
+ "Use slot-exists? instead.")
+ (check-slot-args class obj slot-name)
+ (slot-exists? obj slot-name)))
+
+
+\f
+
+;;;
+;;; Method accessors.
+;;;
+(define (method-generic-function obj)
+ "Return the generic function for the method @var{obj}."
+ (unless (is-a? obj <method>)
+ (scm-error 'wrong-type-arg #f "Not a method: ~S"
+ (list obj) #f))
+ (slot-ref obj 'generic-function))
+
+(define (method-specializers obj)
+ "Return specializers of the method @var{obj}."
+ (unless (is-a? obj <method>)
+ (scm-error 'wrong-type-arg #f "Not a method: ~S"
+ (list obj) #f))
+ (slot-ref obj 'specializers))
+
+(define (method-procedure obj)
+ "Return the procedure of the method @var{obj}."
+ (unless (is-a? obj <method>)
+ (scm-error 'wrong-type-arg #f "Not a method: ~S"
+ (list obj) #f))
+ (slot-ref obj 'procedure))
+
+
+\f
+
+;;;
+;;; Generic functions!
+;;;
+;;; Generic functions have an applicable-methods cache associated with
+;;; them. Every distinct set of types that is dispatched through a
+;;; generic adds an entry to the cache. A composite dispatch procedure
+;;; is recomputed every time an entry gets added to the cache, or when
+;;; the cache is invalidated.
+;;;
+;;; In steady-state, this dispatch procedure is never regenerated; but
+;;; during warm-up there is some churn.
+;;;
+;;; So what is the deal if warm-up happens in a multithreaded context?
+;;; There is indeed a window between missing the cache for a certain set
+;;; of arguments, and then updating the cache with the newly computed
+;;; applicable methods. One of the updaters is liable to lose their new
+;;; entry.
+;;;
+;;; This is actually OK though, because a subsequent cache miss for the
+;;; race loser will just cause memoization to try again. The cache will
+;;; eventually be consistent. We're not mutating the old part of the
+;;; cache, just consing on the new entry.
+;;;
+;;; It doesn't even matter if the dispatch procedure and the cache are
+;;; inconsistent -- most likely the type-set that lost the dispatch
+;;; procedure race will simply re-trigger a memoization, but since the
+;;; winner isn't in the effective-methods cache, it will likely also
+;;; re-trigger a memoization, and the cache will finally be consistent.
+;;; As you can see there is a possibility for ping-pong effects, but
+;;; it's unlikely given the shortness of the window between slot-set!
+;;; invocations.
+;;;
+;;; We probably do need to use atomic access primitives to correctly
+;;; handle concurrency, but that's a more general Guile concern.
+;;;
+
+(define-syntax arity-case
+ (lambda (x)
+ (syntax-case x ()
+ ;; (arity-case n 2 foo bar)
+ ;; => (case n
+ ;; ((0) (foo))
+ ;; ((1) (foo a))
+ ;; ((2) (foo a b))
+ ;; (else bar))
+ ((arity-case n max form alternate)
+ (let ((max (syntax->datum #'max)))
+ #`(case n
+ #,@(let lp ((n 0))
+ (let ((ids (map (lambda (n)
+ (let* ((n (+ (char->integer #\a) n))
+ (c (integer->char n)))
+ (datum->syntax #'here (symbol c))))
+ (iota n))))
+ #`(((#,n) (form #,@ids))
+ . #,(if (< n max)
+ (lp (1+ n))
+ #'()))))
+ (else alternate)))))))
+
+;;;
+;;; These dispatchers are set as the "procedure" field of <generic>
+;;; instances. Unlike CLOS, in GOOPS a generic function can have
+;;; multiple arities.
+;;;
+;;; We pre-generate fast dispatchers for applications of up to 20
+;;; arguments. More arguments than that will go through slower generic
+;;; routines that cons arguments into a rest list.
+;;;
+(define (multiple-arity-dispatcher fv miss)
+ (define-syntax dispatch
+ (lambda (x)
+ (define (build-clauses args)
+ (let ((len (length (syntax->datum args))))
+ #`((#,args ((vector-ref fv #,len) . #,args))
+ . #,(syntax-case args ()
+ (() #'())
+ ((arg ... _) (build-clauses #'(arg ...)))))))
+ (syntax-case x ()
+ ((dispatch arg ...)
+ #`(case-lambda
+ #,@(build-clauses #'(arg ...))
+ (args (apply miss args)))))))
+ (arity-case (vector-length fv) 20 dispatch
+ (lambda args
+ (let ((nargs (length args)))
+ (if (< nargs (vector-length fv))
+ (apply (vector-ref fv nargs) args)
+ (apply miss args))))))
+
+;;;
+;;; The above multiple-arity-dispatcher is entirely sufficient, and
+;;; should be fast enough. Still, for no good reason we also have an
+;;; arity dispatcher for generics that are only called with one arity.
+;;;
+(define (single-arity-dispatcher f nargs miss)
+ (define-syntax-rule (dispatch arg ...)
+ (case-lambda
+ ((arg ...) (f arg ...))
+ (args (apply miss args))))
+ (arity-case nargs 20 dispatch
+ (lambda args
+ (if (eqv? (length args) nargs)
+ (apply f args)
+ (apply miss args)))))
+
+;;;
+;;; The guts of generic function dispatch are here. Once we've selected
+;;; an arity, we need to map from arguments to effective method. Until
+;;; we have `eqv?' specializers, this map is entirely a function of the
+;;; types (classes) of the arguments. So, we look in the cache to see
+;;; if we have seen this set of concrete types, and if so we apply the
+;;; previously computed effective method. Otherwise we miss the cache,
+;;; so we'll have to compute the right answer for this set of types, add
+;;; the mapping to the cache, and apply the newly computed method.
+;;;
+;;; The cached mapping is invalidated whenever a new method is defined
+;;; on this generic, or whenever the class hierarchy of any method
+;;; specializer changes.
+;;;
+(define (single-arity-cache-dispatch cache nargs cache-miss)
+ (match cache
+ (() cache-miss)
+ (((typev . cmethod) . cache)
+ (cond
+ ((eqv? nargs (vector-length typev))
+ (let ((cache-miss (single-arity-cache-dispatch cache nargs cache-miss)))
+ (define (type-ref n)
+ (and (< n nargs) (vector-ref typev n)))
+ (define-syntax args-match?
+ (syntax-rules ()
+ ((args-match?) #t)
+ ((args-match? (arg type) (arg* type*) ...)
+ ;; Check that the arg has the exact type that we saw. It
+ ;; could be that `type' is #f, which indicates the end of
+ ;; the specializers list. Once all specializers have been
+ ;; examined, we don't need to look at any more arguments
+ ;; to know that this is a cache hit.
+ (or (not type)
+ (and (eq? (class-of arg) type)
+ (args-match? (arg* type*) ...))))))
+ (define-syntax dispatch
+ (lambda (x)
+ (define (bind-types types k)
+ (let lp ((types types) (n 0))
+ (syntax-case types ()
+ (() (k))
+ ((type . types)
+ #`(let ((type (type-ref #,n)))
+ #,(lp #'types (1+ n)))))))
+ (syntax-case x ()
+ ((dispatch arg ...)
+ (with-syntax (((type ...) (generate-temporaries #'(arg ...))))
+ (bind-types
+ #'(type ...)
+ (lambda ()
+ #'(lambda (arg ...)
+ (if (args-match? (arg type) ...)
+ (cmethod arg ...)
+ (cache-miss arg ...))))))))))
+ (arity-case nargs 20 dispatch
+ (lambda args
+ (define (args-match? args)
+ (let lp ((args args) (n 0))
+ (match args
+ ((arg . args)
+ (or (not (vector-ref typev n))
+ (and (eq? (vector-ref typev n) (class-of arg))
+ (lp args (1+ n)))))
+ (_ #t))))
+ (if (args-match? args)
+ (apply cmethod args)
+ (apply cache-miss args))))))
+ (else
+ (single-arity-cache-dispatch cache nargs cache-miss))))))
+
+(define (compute-generic-function-dispatch-procedure gf)
+ (define (seen-arities cache)
+ (let lp ((arities 0) (cache cache))
+ (match cache
+ (() arities)
+ (((typev . cmethod) . cache)
+ (lp (logior arities (ash 1 (vector-length typev)))
+ cache)))))
+ (define (cache-miss . args)
+ (memoize-generic-function-application! gf args)
+ (apply gf args))
+ (let* ((cache (slot-ref gf 'effective-methods))
+ (arities (seen-arities cache))
+ (max-arity (let lp ((max -1))
+ (if (< arities (ash 1 (1+ max)))
+ max
+ (lp (1+ max))))))
+ (cond
+ ((= max-arity -1)
+ ;; Nothing in the cache.
+ cache-miss)
+ ((= arities (ash 1 max-arity))
+ ;; Only one arity in the cache.
+ (let* ((nargs max-arity)
+ (f (single-arity-cache-dispatch cache nargs cache-miss)))
+ (single-arity-dispatcher f nargs cache-miss)))
+ (else
+ ;; Multiple arities.
+ (let ((fv (make-vector (1+ max-arity) #f)))
+ (let lp ((n 0))
+ (when (<= n max-arity)
+ (let ((f (single-arity-cache-dispatch cache n cache-miss)))
+ (vector-set! fv n f)
+ (lp (1+ n)))))
+ (multiple-arity-dispatcher fv cache-miss))))))
+
+(define (recompute-generic-function-dispatch-procedure! gf)
+ (slot-set! gf 'procedure
+ (compute-generic-function-dispatch-procedure gf)))
+
+(define (memoize-effective-method! gf args applicable)
+ (define (record-types args)
+ (let ((typev (make-vector (length args) #f)))
+ (let lp ((n 0) (args args))
+ (when (and (< n (slot-ref gf 'n-specialized))
+ (pair? args))
+ (match args
+ ((arg . args)
+ (vector-set! typev n (class-of arg))
+ (lp (1+ n) args)))))
+ typev))
+ (let* ((typev (record-types args))
+ (compute-effective-method (if (eq? (class-of gf) <generic>)
+ %compute-effective-method
+ compute-effective-method))
+ (cmethod (compute-effective-method gf applicable typev))
+ (cache (acons typev cmethod (slot-ref gf 'effective-methods))))
+ (slot-set! gf 'effective-methods cache)
+ (recompute-generic-function-dispatch-procedure! gf)
+ cmethod))
+
+;;;
+;;; If a method refers to `next-method' in its body, that method will be
+;;; able to dispatch to the next most specific method. The exact
+;;; `next-method' implementation is only known at runtime, as it is a
+;;; function of which precise argument types are being dispatched, which
+;;; might be subclasses of the method's declared specializers.
+;;;
+;;; Guile implements `next-method' by binding it as a closure variable.
+;;; An effective method is bound to a specific `next-method' by the
+;;; `make-procedure' slot of a <method>, which returns the new closure.
+;;;
+(define (%compute-specialized-effective-method gf method types next-method)
+ (match (slot-ref method 'make-procedure)
+ (#f (method-procedure method))
+ (make-procedure (make-procedure next-method))))
+
+(define (compute-specialized-effective-method gf method types next-method)
+ (%compute-specialized-effective-method gf method types next-method))
+
+(define (%compute-effective-method gf methods types)
(match methods
((method . methods)
- (let ((make-procedure (slot-ref method 'make-procedure)))
- (if make-procedure
- (make-procedure
- (if (null? methods)
- (lambda args
- (no-next-method (method-generic-function method) args))
- (compute-cmethod methods types)))
- (method-procedure method))))))
+ (let ((compute-specialized-effective-method
+ (if (and (eq? (class-of gf) <generic>)
+ (eq? (class-of method) <method>))
+ %compute-specialized-effective-method
+ compute-specialized-effective-method)))
+ (compute-specialized-effective-method
+ gf method types
+ (match methods
+ (()
+ (lambda args
+ (no-next-method gf args)))
+ (methods
+ (let ((compute-effective-method (if (eq? (class-of gf) <generic>)
+ %compute-effective-method
+ compute-effective-method)))
+ (compute-effective-method gf methods types)))))))))
+
+;; Boot definition; overrided with a generic later.
+(define (compute-effective-method gf methods types)
+ (%compute-effective-method gf methods types))
+
+;;;
+;;; Memoization
+;;;
+
+(define (memoize-generic-function-application! gf args)
+ (let ((applicable ((if (eq? (class-of gf) <generic>)
+ %compute-applicable-methods
+ compute-applicable-methods)
+ gf args)))
+ (cond (applicable
+ (memoize-effective-method! gf args applicable))
+ (else
+ (no-applicable-method gf args)))))
+
+(define no-applicable-method
+ (make <generic> #:name 'no-applicable-method))
+
+(%goops-early-init)
+
+;; Then load the rest of GOOPS
\f
-(eval-when (expand load eval)
- (define min-fixnum (- (expt 2 29)))
- (define max-fixnum (- (expt 2 29) 1)))
+;; FIXME: deprecate.
+(define min-fixnum (- (expt 2 29)))
+(define max-fixnum (- (expt 2 29) 1))
;;
;; goops-error
(define (goops-error format-string . args)
(scm-error 'goops-error #f format-string args '()))
-;;
-;; is-a?
-;;
-(define (is-a? obj class)
- (and (memq class (class-precedence-list (class-of obj))) #t))
-
-
;;;
;;; {Meta classes}
;;;
(let ((table-of-metas '()))
(lambda (meta-supers)
(let ((entry (assoc meta-supers table-of-metas)))
- (if entry
- ;; Found a previously created metaclass
- (cdr entry)
- ;; Create a new meta-class which inherit from "meta-supers"
- (let ((new (make <class> #:dsupers meta-supers
- #:slots '()
- #:name (gensym "metaclass"))))
- (set! table-of-metas (cons (cons meta-supers new) table-of-metas))
- new))))))
+ (if entry
+ ;; Found a previously created metaclass
+ (cdr entry)
+ ;; Create a new meta-class which inherit from "meta-supers"
+ (let ((new (make <class> #:dsupers meta-supers
+ #:slots '()
+ #:name (gensym "metaclass"))))
+ (set! table-of-metas (cons (cons meta-supers new) table-of-metas))
+ new))))))
(define (ensure-metaclass supers)
(if (null? supers)
<class>
(let* ((all-metas (map (lambda (x) (class-of x)) supers))
- (all-cpls (append-map (lambda (m)
- (cdr (class-precedence-list m)))
+ (all-cpls (append-map (lambda (m)
+ (cdr (class-precedence-list m)))
all-metas))
- (needed-metas '()))
- ;; Find the most specific metaclasses. The new metaclass will be
- ;; a subclass of these.
- (for-each
- (lambda (meta)
- (if (and (not (member meta all-cpls))
- (not (member meta needed-metas)))
- (set! needed-metas (append needed-metas (list meta)))))
- all-metas)
- ;; Now return a subclass of the metaclasses we found.
- (if (null? (cdr needed-metas))
- (car needed-metas) ; If there's only one, just use it.
- (ensure-metaclass-with-supers needed-metas)))))
+ (needed-metas '()))
+ ;; Find the most specific metaclasses. The new metaclass will be
+ ;; a subclass of these.
+ (for-each
+ (lambda (meta)
+ (when (and (not (member meta all-cpls))
+ (not (member meta needed-metas)))
+ (set! needed-metas (append needed-metas (list meta)))))
+ all-metas)
+ ;; Now return a subclass of the metaclasses we found.
+ (if (null? (cdr needed-metas))
+ (car needed-metas) ; If there's only one, just use it.
+ (ensure-metaclass-with-supers needed-metas)))))
;;;
;;; {Classes}
;;; (define-class NAME (SUPER ...) SLOT-DEFINITION ... OPTION ...)
;;;
-;;; SLOT-DEFINITION ::= SLOT-NAME | (SLOT-NAME OPTION ...)
+;;; SLOT-DEFINITION ::= INSTANCE-OF-<SLOT> | (SLOT-NAME OPTION ...)
;;; OPTION ::= KEYWORD VALUE
;;;
-(define (kw-do-map mapper f kwargs)
- (define (keywords l)
- (cond
- ((null? l) '())
- ((or (null? (cdr l)) (not (keyword? (car l))))
- (goops-error "malformed keyword arguments: ~a" kwargs))
- (else (cons (car l) (keywords (cddr l))))))
- (define (args l)
- (if (null? l) '() (cons (cadr l) (args (cddr l)))))
- ;; let* to check keywords first
- (let* ((k (keywords kwargs))
- (a (args kwargs)))
- (mapper f k a)))
-
(define (make-class supers slots . options)
- (let* ((name (get-keyword #:name options (make-unbound)))
+ (define (find-duplicate l)
+ (match l
+ (() #f)
+ ((head . tail)
+ (if (memq head tail)
+ head
+ (find-duplicate tail)))))
+ (define (slot-spec->name slot-spec)
+ (match slot-spec
+ (((? symbol? name) . args) name)
+ ;; We can get here when redefining classes.
+ ((? slot? slot) (%slot-definition-name slot))))
+
+ (let* ((name (get-keyword #:name options *unbound*))
(supers (if (not (or-map (lambda (class)
(memq <object>
(class-precedence-list class)))
;; Verify that all direct slots are different and that we don't inherit
;; several time from the same class
(let ((tmp1 (find-duplicate supers))
- (tmp2 (find-duplicate (map slot-definition-name slots))))
+ (tmp2 (find-duplicate (map slot-spec->name slots))))
(if tmp1
(goops-error "make-class: super class ~S is duplicate in class ~S"
tmp1 name))
;; Everything seems correct, build the class
(apply make metaclass
#:dsupers supers
- #:slots slots
+ #:slots slots
#:name name
options)))
;;; SLOT-DEFINITION ::= SLOT-NAME | (SLOT-NAME OPTION ...)
;;; OPTION ::= KEYWORD VALUE
;;;
-(define-macro (class supers . slots)
- (define (make-slot-definition-forms slots)
- (map
- (lambda (def)
- (cond
- ((pair? def)
- `(list ',(car def)
- ,@(kw-do-map append-map
- (lambda (kw arg)
- (case kw
- ((#:init-form)
- `(#:init-form ',arg
- #:init-thunk (lambda () ,arg)))
- (else (list kw arg))))
- (cdr def))))
- (else
- `(list ',def))))
- slots))
- (if (not (list? supers))
- (goops-error "malformed superclass list: ~S" supers))
- (let ((slots (take-while (lambda (x) (not (keyword? x))) slots))
- (options (or (find-tail keyword? slots) '())))
- `(make-class
- ;; evaluate super class variables
- (list ,@supers)
- ;; evaluate slot definitions, except the slot name!
- (list ,@(make-slot-definition-forms slots))
- ;; evaluate class options
- ,@options)))
+(define-syntax class
+ (lambda (x)
+ (define (parse-options options)
+ (syntax-case options ()
+ (() #'())
+ ((kw arg . options) (keyword? (syntax->datum #'kw))
+ (with-syntax ((options (parse-options #'options)))
+ (syntax-case #'kw ()
+ (#:init-form
+ #'(kw 'arg #:init-thunk (lambda () arg) . options))
+ (_
+ #'(kw arg . options)))))))
+ (define (check-valid-kwargs args)
+ (syntax-case args ()
+ (() #'())
+ ((kw arg . args) (keyword? (syntax->datum #'kw))
+ #`(kw arg . #,(check-valid-kwargs #'args)))))
+ (define (parse-slots-and-kwargs args)
+ (syntax-case args ()
+ (()
+ #'(() ()))
+ ((kw . _) (keyword? (syntax->datum #'kw))
+ #`(() #,(check-valid-kwargs args)))
+ (((name option ...) args ...)
+ (with-syntax (((slots kwargs) (parse-slots-and-kwargs #'(args ...)))
+ ((option ...) (parse-options #'(option ...))))
+ #'(((list 'name option ...) . slots) kwargs)))
+ ((name args ...) (symbol? (syntax->datum #'name))
+ (with-syntax (((slots kwargs) (parse-slots-and-kwargs #'(args ...))))
+ #'(('(name) . slots) kwargs)))))
+ (syntax-case x ()
+ ((class (super ...) arg ...)
+ (with-syntax ((((slot-def ...) (option ...))
+ (parse-slots-and-kwargs #'(arg ...))))
+ #'(make-class (list super ...)
+ (list slot-def ...)
+ option ...))))))
(define-syntax define-class-pre-definition
(lambda (x)
((#:getter #:setter)
#'(define-class-pre-definition (rest ...)
out ...
- (if (or (not (defined? 'arg))
- (not (is-a? arg <generic>)))
- (toplevel-define!
- 'arg
- (ensure-generic (if (defined? 'arg) arg #f) 'arg)))))
+ (when (or (not (defined? 'arg))
+ (not (is-a? arg <generic>)))
+ (toplevel-define!
+ 'arg
+ (ensure-generic (if (defined? 'arg) arg #f) 'arg)))))
((#:accessor)
#'(define-class-pre-definition (rest ...)
out ...
- (if (or (not (defined? 'arg))
- (not (is-a? arg <accessor>)))
- (toplevel-define!
- 'arg
- (ensure-accessor (if (defined? 'arg) arg #f) 'arg)))))
+ (when (or (not (defined? 'arg))
+
(not (is-a? arg <accessor>)))
+ (toplevel-define!
+ 'arg
+ (ensure-accessor (if (defined? 'arg) arg #f) 'arg)))))
(else
#'(define-class-pre-definition (rest ...) out ...))))
((_ () out ...)
#'(begin out ...)))))
-
+
;; Some slot options require extra definitions to be made. In
;; particular, we want to make sure that the generic function objects
;; which represent accessors exist before `make-class' tries to add
#'(define-class-pre-definitions (rest ...)
out ...))
((_ ((slotname slotopt ...) rest ...) out ...)
- #'(define-class-pre-definitions (rest ...)
+ #'(define-class-pre-definitions (rest ...)
out ... (define-class-pre-definition (slotopt ...)))))))
(define-syntax-rule (define-class name supers slot ...)
(class-redefinition name
(class supers slot ... #:name 'name))
(toplevel-define! 'name (class supers slot ... #:name 'name)))))
-
+
(define-syntax-rule (standard-define-class arg ...)
(define-class arg ...))
;; Apparently the desired semantics are that we extend previous
;; procedural definitions, but that if `name' was already a generic, we
;; overwrite its definition.
-(define-macro (define-generic name)
- (if (not (symbol? name))
- (goops-error "bad generic function name: ~S" name))
- `(define ,name
- (if (and (defined? ',name) (is-a? ,name <generic>))
- (make <generic> #:name ',name)
- (ensure-generic (if (defined? ',name) ,name #f) ',name))))
-
-(define-macro (define-extended-generic name val)
- (if (not (symbol? name))
- (goops-error "bad generic function name: ~S" name))
- `(define ,name (make-extended-generic ,val ',name)))
-
-(define-macro (define-extended-generics names . args)
- (let ((prefixes (get-keyword #:prefix args #f)))
- (if prefixes
- `(begin
- ,@(map (lambda (name)
- `(define-extended-generic ,name
- (list ,@(map (lambda (prefix)
- (symbol-append prefix name))
- prefixes))))
- names))
- (goops-error "no prefixes supplied"))))
+(define-syntax define-generic
+ (lambda (x)
+ (syntax-case x ()
+ ((define-generic name) (symbol? (syntax->datum #'name))
+ #'(define name
+ (if (and (defined? 'name) (is-a? name <generic>))
+ (make <generic> #:name 'name)
+ (ensure-generic (if (defined? 'name) name #f) 'name)))))))
+
+(define-syntax define-extended-generic
+ (lambda (x)
+ (syntax-case x ()
+ ((define-extended-generic name val) (symbol? (syntax->datum #'name))
+ #'(define name (make-extended-generic val 'name))))))
+
+(define-syntax define-extended-generics
+ (lambda (x)
+ (define (id-append ctx a b)
+ (datum->syntax ctx (symbol-append (syntax->datum a) (syntax->datum b))))
+ (syntax-case x ()
+ ((define-extended-generic (name ...) #:prefix (prefix ...))
+ (and (and-map symbol? (syntax->datum #'(name ...)))
+ (and-map symbol? (syntax->datum #'(prefix ...))))
+ (with-syntax ((((val ...)) (map (lambda (name)
+ (map (lambda (prefix)
+ (id-append name prefix name))
+ #'(prefix ...)))
+ #'(name ...))))
+ #'(begin
+ (define-extended-generic name (list val ...))
+ ...))))))
(define* (make-generic #:optional name)
(make <generic> #:name name))
(define* (make-extended-generic gfs #:optional name)
(let* ((gfs (if (list? gfs) gfs (list gfs)))
- (gws? (any (lambda (gf) (is-a? gf <generic-with-setter>)) gfs)))
+ (gws? (any (lambda (gf) (is-a? gf <generic-with-setter>)) gfs)))
(let ((ans (if gws?
- (let* ((sname (and name (make-setter-name name)))
- (setters
- (append-map (lambda (gf)
- (if (is-a? gf <generic-with-setter>)
- (list (ensure-generic (setter gf)
- sname))
- '()))
- gfs))
- (es (make <extended-generic-with-setter>
- #:name name
- #:extends gfs
- #:setter (make <extended-generic>
- #:name sname
- #:extends setters))))
- (extended-by! setters (setter es))
- es)
- (make <extended-generic>
- #:name name
- #:extends gfs))))
+ (let* ((sname (and name (make-setter-name name)))
+ (setters
+ (append-map (lambda (gf)
+ (if (is-a? gf <generic-with-setter>)
+ (list (ensure-generic (setter gf)
+ sname))
+ '()))
+ gfs))
+ (es (make <extended-generic-with-setter>
+ #:name name
+ #:extends gfs
+ #:setter (make <extended-generic>
+ #:name sname
+ #:extends setters))))
+ (extended-by! setters (setter es))
+ es)
+ (make <extended-generic>
+ #:name name
+ #:extends gfs))))
(extended-by! gfs ans)
ans)))
(define (extended-by! gfs eg)
(for-each (lambda (gf)
- (slot-set! gf 'extended-by
- (cons eg (slot-ref gf 'extended-by))))
- gfs)
+ (slot-set! gf 'extended-by
+ (cons eg (slot-ref gf 'extended-by))))
+ gfs)
(invalidate-method-cache! eg))
(define (not-extended-by! gfs eg)
(for-each (lambda (gf)
- (slot-set! gf 'extended-by
- (delq! eg (slot-ref gf 'extended-by))))
- gfs)
+ (slot-set! gf 'extended-by
+ (delq! eg (slot-ref gf 'extended-by))))
+ gfs)
(invalidate-method-cache! eg))
(define* (ensure-generic old-definition #:optional name)
(define (upgrade-accessor generic setter)
(let ((methods (slot-ref generic 'methods))
- (gws (make (if (is-a? generic <extended-generic>)
- <extended-generic-with-setter>
- <accessor>)
- #:name (generic-function-name generic)
- #:extended-by (slot-ref generic 'extended-by)
- #:setter setter)))
- (if (is-a? generic <extended-generic>)
- (let ((gfs (slot-ref generic 'extends)))
- (not-extended-by! gfs generic)
- (slot-set! gws 'extends gfs)
- (extended-by! gfs gws)))
+ (gws (make (if (is-a? generic <extended-generic>)
+ <extended-generic-with-setter>
+ #:name (generic-function-name generic)
+ #:extended-by (slot-ref generic 'extended-by)
+ #:setter setter)))
+ (when (is-a? generic <extended-generic>)
+ (let ((gfs (slot-ref generic 'extends)))
+ (not-extended-by! gfs generic)
+ (slot-set! gws 'extends gfs)
+ (extended-by! gfs gws)))
;; Steal old methods
(for-each (lambda (method)
- (slot-set! method 'generic-function gws))
- methods)
+ (slot-set! method 'generic-function gws))
+ methods)
(slot-set! gws 'methods methods)
(invalidate-method-cache! gws)
gws))
;;; {Methods}
;;;
+;; Note: `a' and `b' can have unequal lengths (i.e. one can be one
+;; element longer than the other when we have a dotted parameter
+;; list). For instance, with the call
+;;
+;; (M 1)
+;;
+;; with
+;;
+;; (define-method M (a . l) ....)
+;; (define-method M (a) ....)
+;;
+;; we consider that the second method is more specific.
+;;
+;; Precondition: `a' and `b' are methods and are applicable to `types'.
+(define (%method-more-specific? a b types)
+ (let lp ((a-specializers (method-specializers a))
+ (b-specializers (method-specializers b))
+ (types types))
+ (cond
+ ;; (a) less specific than (a b ...) or (a . b)
+ ((null? a-specializers) #t)
+ ;; (a b ...) or (a . b) less specific than (a)
+ ((null? b-specializers) #f)
+ ;; (a . b) less specific than (a b ...)
+ ((not (pair? a-specializers)) #f)
+ ;; (a b ...) more specific than (a . b)
+ ((not (pair? b-specializers)) #t)
+ (else
+ (let ((a-specializer (car a-specializers))
+ (b-specializer (car b-specializers))
+ (a-specializers (cdr a-specializers))
+ (b-specializers (cdr b-specializers))
+ (type (car types))
+ (types (cdr types)))
+ (if (eq? a-specializer b-specializer)
+ (lp a-specializers b-specializers types)
+ (let lp ((cpl (class-precedence-list type)))
+ (let ((elt (car cpl)))
+ (cond
+ ((eq? a-specializer elt) #t)
+ ((eq? b-specializer elt) #f)
+ (else (lp (cdr cpl))))))))))))
+
+(define (%sort-applicable-methods methods types)
+ (sort methods (lambda (a b) (%method-more-specific? a b types))))
+
+(define (generic-function-methods obj)
+ "Return the methods of the generic function @var{obj}."
+ (define (fold-upward method-lists gf)
+ (cond
+ ((is-a? gf <extended-generic>)
+ (let lp ((method-lists method-lists) (gfs (slot-ref gf 'extends)))
+ (match gfs
+ (() method-lists)
+ ((gf . gfs)
+ (lp (fold-upward (cons (slot-ref gf 'methods) method-lists) gf)
+ gfs)))))
+ (else method-lists)))
+ (define (fold-downward method-lists gf)
+ (let lp ((method-lists (cons (slot-ref gf 'methods) method-lists))
+ (gfs (slot-ref gf 'extended-by)))
+ (match gfs
+ (() method-lists)
+ ((gf . gfs)
+ (lp (fold-downward method-lists gf) gfs)))))
+ (unless (is-a? obj <generic>)
+ (scm-error 'wrong-type-arg #f "Not a generic: ~S"
+ (list obj) #f))
+ (concatenate (fold-downward (fold-upward '() obj) obj)))
+
+(define (%compute-applicable-methods gf args)
+ (define (method-applicable? m types)
+ (let ((specs (method-specializers m)))
+ (cond
+ ((and (is-a? m <accessor-method>)
+ (or (null? specs) (null? types)
+ (not (eq? (car specs) (car types)))))
+ ;; Slot accessor methods are added to each subclass with the
+ ;; slot. They only apply to that specific concrete class, which
+ ;; appears as the first argument.
+ #f)
+ (else
+ (let lp ((specs specs) (types types))
+ (cond
+ ((null? specs) (null? types))
+ ((not (pair? specs)) #t)
+ ((null? types) #f)
+ (else
+ (and (memq (car specs) (class-precedence-list (car types)))
+ (lp (cdr specs) (cdr types))))))))))
+ (let ((n (length args))
+ (types (map class-of args)))
+ (let lp ((methods (generic-function-methods gf))
+ (applicable '()))
+ (if (null? methods)
+ (and (not (null? applicable))
+ (%sort-applicable-methods applicable types))
+ (let ((m (car methods)))
+ (lp (cdr methods)
+ (if (method-applicable? m types)
+ (cons m applicable)
+ applicable)))))))
+
+(define compute-applicable-methods %compute-applicable-methods)
+
(define (toplevel-define! name val)
(module-define! (current-module) name val))
(syntax-rules (setter)
((_ ((setter name) . args) body ...)
(begin
- (if (or (not (defined? 'name))
- (not (is-a? name <accessor>)))
- (toplevel-define! 'name
- (ensure-accessor
- (if (defined? 'name) name #f) 'name)))
+ (when (or (not (defined? 'name))
+
(not (is-a? name <accessor>)))
+ (toplevel-define! 'name
+ (ensure-accessor
+ (if (defined? 'name) name #f) 'name)))
(add-method! (setter name) (method args body ...))))
((_ (name . args) body ...)
(begin
;; before (ok), or *was defined to #f*. The latter is crack. But
;; there are bootstrap issues about fixing this -- change it to
;; (is-a? name <generic>) and see.
- (if (or (not (defined? 'name))
- (not name))
- (toplevel-define! 'name (make <generic> #:name 'name)))
+ (when (or (not (defined? 'name))
+ (not name))
+ (toplevel-define! 'name (make <generic> #:name 'name)))
(add-method! name (method args body ...))))))
(define-syntax method
#:make-procedure make-procedure
#:procedure procedure)))))))))
+;;;
+;;; {Utilities}
+;;;
+;;; These are useful when dealing with method specializers, which might
+;;; have a rest argument.
+;;;
+
+(define (map* fn . l) ; A map which accepts dotted lists (arg lists
+ (cond ; must be "isomorph"
+ ((null? (car l)) '())
+ ((pair? (car l)) (cons (apply fn (map car l))
+ (apply map* fn (map cdr l))))
+ (else (apply fn l))))
+
+(define (for-each* fn . l) ; A for-each which accepts dotted lists (arg lists
+ (cond ; must be "isomorph"
+ ((null? (car l)) '())
+ ((pair? (car l)) (apply fn (map car l)) (apply for-each* fn (map cdr l)))
+ (else (apply fn l))))
+
+(define (length* ls)
+ (do ((n 0 (+ 1 n))
+ (ls ls (cdr ls)))
+ ((not (pair? ls)) n)))
+
;;;
;;; {add-method!}
;;;
(define (add-method-in-classes! m)
;; Add method in all the classes which appears in its specializers list
(for-each* (lambda (x)
- (let ((dm (class-direct-methods x)))
- (if (not (memq m dm))
- (slot-set! x 'direct-methods (cons m dm)))))
- (method-specializers m)))
+ (let ((dm (class-direct-methods x)))
+ (unless (memq m dm)
+ (struct-set! x class-index-direct-methods (cons m dm)))))
+ (method-specializers m)))
(define (remove-method-in-classes! m)
;; Remove method in all the classes which appears in its specializers list
(for-each* (lambda (x)
- (slot-set! x
- 'direct-methods
- (delv! m (class-direct-methods x))))
- (method-specializers m)))
+ (struct-set! x
+ class-index-direct-methods
+ (delv! m (class-direct-methods x))))
+ (method-specializers m)))
(define (compute-new-list-of-methods gf new)
(let ((new-spec (method-specializers new))
- (methods (slot-ref gf 'methods)))
+ (methods (slot-ref gf 'methods)))
(let loop ((l methods))
(if (null? l)
- (cons new methods)
- (if (equal? (method-specializers (car l)) new-spec)
- (begin
- ;; This spec. list already exists. Remove old method from dependents
- (remove-method-in-classes! (car l))
- (set-car! l new)
- methods)
- (loop (cdr l)))))))
+ (cons new methods)
+ (if (equal? (method-specializers (car l)) new-spec)
+ (begin
+ ;; This spec. list already exists. Remove old method from dependents
+ (remove-method-in-classes! (car l))
+ (set-car! l new)
+ methods)
+ (loop (cdr l)))))))
(define (method-n-specializers m)
(length* (slot-ref m 'specializers)))
(generic-function-methods gf)))
(define (invalidate-method-cache! gf)
- (%invalidate-method-cache! gf)
(slot-set! gf 'n-specialized (calculate-n-specialized gf))
+ (%invalidate-method-cache! gf)
(for-each (lambda (gf) (invalidate-method-cache! gf))
(slot-ref gf 'extended-by)))
(define-method (add-method! (proc <procedure>) (m <method>))
(if (generic-capability? proc)
(begin
- (enable-primitive-generic! proc)
- (add-method! proc m))
+ (enable-primitive-generic! proc)
+ (add-method! proc m))
(next-method)))
(define-method (add-method! (pg <primitive-generic>) (m <method>))
;;;
(define-method (method-source (m <method>))
(let* ((spec (map* class-name (slot-ref m 'specializers)))
- (src (procedure-source (slot-ref m 'procedure))))
+ (src (procedure-source (slot-ref m 'procedure))))
(and src
(let ((args (cadr src))
(body (cddr src)))
;;;
;;; Slots
;;;
-(define slot-definition-name car)
-
-(define slot-definition-options cdr)
-
-(define (slot-definition-allocation s)
- (get-keyword #:allocation (cdr s) #:instance))
-
-(define (slot-definition-getter s)
- (get-keyword #:getter (cdr s) #f))
-
-(define (slot-definition-setter s)
- (get-keyword #:setter (cdr s) #f))
-
-(define (slot-definition-accessor s)
- (get-keyword #:accessor (cdr s) #f))
-
-(define (slot-definition-init-value s)
- ;; can be #f, so we can't use #f as non-value
- (get-keyword #:init-value (cdr s) (make-unbound)))
-
-(define (slot-definition-init-form s)
- (get-keyword #:init-form (cdr s) (make-unbound)))
-
-(define (slot-definition-init-thunk s)
- (get-keyword #:init-thunk (cdr s) #f))
-
-(define (slot-definition-init-keyword s)
- (get-keyword #:init-keyword (cdr s) #f))
-
-(define (class-slot-definition class slot-name)
- (assq slot-name (class-slots class)))
-
(define (slot-init-function class slot-name)
- (cadr (assq slot-name (slot-ref class 'getters-n-setters))))
+ (%slot-definition-init-thunk (or (class-slot-definition class slot-name)
+ (error "slot not found" slot-name))))
(define (accessor-method-slot-definition obj)
"Return the slot definition of the accessor @var{obj}."
;; When this generic gets called, we will have already checked eq? and
;; eqv? -- the purpose of this generic is to extend equality. So by
;; default, there is no extension, thus the #f return.
-(add-method! g-equal? (method (x y) #f))
+(add-method! g-equal? (method (x y) #f))
(set-primitive-generic! equal? g-equal?)
;;;
;;;
; Code for writing objects must test that the slots they use are
-; bound. Otherwise a slot-unbound method will be called and will
+; bound. Otherwise a slot-unbound method will be called and will
; conduct to an infinite loop.
;; Write
(define-method (write (o <object>) file)
(let ((class (class-of o)))
(if (slot-bound? class 'name)
- (begin
- (display "#<" file)
- (display (class-name class) file)
- (display #\space file)
- (display-address o file)
- (display #\> file))
- (next-method))))
+ (begin
+ (display "#<" file)
+ (display (class-name class) file)
+ (display #\space file)
+ (display-address o file)
+ (display #\> file))
+ (next-method))))
+
+(define-method (write (slot <slot>) file)
+ (let ((class (class-of slot)))
+ (if (and (slot-bound? class 'name)
+ (slot-bound? slot 'name))
+ (begin
+ (display "#<" file)
+ (display (class-name class) file)
+ (display #\space file)
+ (display (%slot-definition-name slot) file)
+ (display #\space file)
+ (display-address slot file)
+ (display #\> file))
+ (next-method))))
(define-method (write (class <class>) file)
(let ((meta (class-of class)))
(if (and (slot-bound? class 'name)
- (slot-bound? meta 'name))
- (begin
- (display "#<" file)
- (display (class-name meta) file)
- (display #\space file)
- (display (class-name class) file)
- (display #\space file)
- (display-address class file)
- (display #\> file))
- (next-method))))
+ (slot-bound? meta 'name))
+ (begin
+ (display "#<" file)
+ (display (class-name meta) file)
+ (display #\space file)
+ (display (class-name class) file)
+ (display #\space file)
+ (display-address class file)
+ (display #\> file))
+ (next-method))))
(define-method (write (gf <generic>) file)
(let ((meta (class-of gf)))
(if (and (slot-bound? meta 'name)
- (slot-bound? gf 'methods))
- (begin
- (display "#<" file)
- (display (class-name meta) file)
- (let ((name (generic-function-name gf)))
- (if name
- (begin
- (display #\space file)
- (display name file))))
- (display " (" file)
- (display (length (generic-function-methods gf)) file)
- (display ")>" file))
- (next-method))))
+ (slot-bound? gf 'methods))
+ (begin
+ (display "#<" file)
+ (display (class-name meta) file)
+ (let ((name (generic-function-name gf)))
+ (if name
+ (begin
+ (display #\space file)
+ (display name file))))
+ (display " (" file)
+ (display (length (generic-function-methods gf)) file)
+ (display ")>" file))
+ (next-method))))
(define-method (write (o <method>) file)
(let ((meta (class-of o)))
(if (and (slot-bound? meta 'name)
- (slot-bound? o 'specializers))
- (begin
- (display "#<" file)
- (display (class-name meta) file)
- (display #\space file)
- (display (map* (lambda (spec)
- (if (slot-bound? spec 'name)
- (slot-ref spec 'name)
- spec))
- (method-specializers o))
- file)
- (display #\space file)
- (display-address o file)
- (display #\> file))
- (next-method))))
+ (slot-bound? o 'specializers))
+ (begin
+ (display "#<" file)
+ (display (class-name meta) file)
+ (display #\space file)
+ (display (map* (lambda (spec)
+ (if (slot-bound? spec 'name)
+ (slot-ref spec 'name)
+ spec))
+ (method-specializers o))
+ file)
+ (display #\space file)
+ (display-address o file)
+ (display #\> file))
+ (next-method))))
;; Display (do the same thing as write by default)
-(define-method (display o file)
+(define-method (display o file)
(write-object o file))
;;;
;;; Handling of duplicate bindings in the module system
;;;
+(define (find-subclass super name)
+ (let lp ((classes (class-direct-subclasses super)))
+ (cond
+ ((null? classes)
+ (error "class not found" name))
+ ((and (slot-bound? (car classes) 'name)
+ (eq? (class-name (car classes)) name))
+ (car classes))
+ (else
+ (lp (cdr classes))))))
+
+;; A record type.
+(define <module> (find-subclass <top> '<module>))
+
(define-method (merge-generics (module <module>)
- (name <symbol>)
- (int1 <module>)
- (val1 <top>)
- (int2 <module>)
- (val2 <top>)
- (var <top>)
- (val <top>))
+ (name <symbol>)
+ (int1 <module>)
+ (val1 <top>)
+ (int2 <module>)
+ (val2 <top>)
+ (var <top>)
+ (val <top>))
#f)
(define-method (merge-generics (module <module>)
- (name <symbol>)
- (int1 <module>)
- (val1 <generic>)
- (int2 <module>)
- (val2 <generic>)
- (var <top>)
- (val <boolean>))
+ (name <symbol>)
+ (int1 <module>)
+ (val1 <generic>)
+ (int2 <module>)
+ (val2 <generic>)
+ (var <top>)
+ (val <boolean>))
(and (not (eq? val1 val2))
(make-variable (make-extended-generic (list val2 val1) name))))
(define-method (merge-generics (module <module>)
- (name <symbol>)
- (int1 <module>)
- (val1 <generic>)
- (int2 <module>)
- (val2 <generic>)
- (var <top>)
- (gf <extended-generic>))
+ (name <symbol>)
+ (int1 <module>)
+ (val1 <generic>)
+ (int2 <module>)
+ (val2 <generic>)
+ (var <top>)
+ (gf <extended-generic>))
(and (not (memq val2 (slot-ref gf 'extends)))
(begin
- (slot-set! gf
- 'extends
- (cons val2 (delq! val2 (slot-ref gf 'extends))))
- (slot-set! val2
- 'extended-by
- (cons gf (delq! gf (slot-ref val2 'extended-by))))
+ (slot-set! gf
+ 'extends
+ (cons val2 (delq! val2 (slot-ref gf 'extends))))
+ (slot-set! val2
+ 'extended-by
+ (cons gf (delq! gf (slot-ref val2 'extended-by))))
(invalidate-method-cache! gf)
- var)))
+ var)))
(module-define! duplicate-handlers 'merge-generics merge-generics)
(define-method (merge-accessors (module <module>)
- (name <symbol>)
- (int1 <module>)
- (val1 <top>)
- (int2 <module>)
- (val2 <top>)
- (var <top>)
- (val <top>))
+ (name <symbol>)
+ (int1 <module>)
+ (val1 <top>)
+ (int2 <module>)
+ (val2 <top>)
+ (var <top>)
+ (val <top>))
#f)
(define-method (merge-accessors (module <module>)
- (name <symbol>)
- (int1 <module>)
- (val1 <accessor>)
- (int2 <module>)
- (val2 <accessor>)
- (var <top>)
- (val <top>))
+ (name <symbol>)
+ (int1 <module>)
+ (int2 <module>)
+ (var <top>)
+ (val <top>))
(merge-generics module name int1 val1 int2 val2 var val))
(module-define! duplicate-handlers 'merge-accessors merge-accessors)
;;; slot access
;;;
-(define (class-slot-g-n-s class slot-name)
- (let* ((this-slot (assq slot-name (slot-ref class 'slots)))
- (g-n-s (cddr (or (assq slot-name (slot-ref class 'getters-n-setters))
- (slot-missing class slot-name)))))
- (if (not (memq (slot-definition-allocation this-slot)
- '(#:class #:each-subclass)))
- (slot-missing class slot-name))
- g-n-s))
-
-(define (class-slot-ref class slot)
- (let ((x ((car (class-slot-g-n-s class slot)) #f)))
- (if (unbound? x)
- (slot-unbound class slot)
- x)))
+(define (class-slot-ref class slot-name)
+ (let ((slot (class-slot-definition class slot-name)))
+ (unless (memq (%slot-definition-allocation slot) '(#:class #:each-subclass))
+ (slot-missing class slot-name))
+ (let ((x ((%slot-definition-slot-ref/raw slot) #f)))
+ (if (unbound? x)
+ (slot-unbound class slot-name)
+ x))))
-(define (class-slot-set! class slot value)
- ((cadr (class-slot-g-n-s class slot)) #f value))
+(define (class-slot-set! class slot-name value)
+ (let ((slot (class-slot-definition class slot-name)))
+ (unless (memq (%slot-definition-allocation slot) '(#:class #:each-subclass))
+ (slot-missing class slot-name))
+ ((%slot-definition-slot-set! slot) #f value)))
(define-method (slot-unbound (c <class>) (o <object>) s)
(goops-error "Slot `~S' is unbound in object ~S" s o))
(define-method (slot-missing (c <class>) (o <object>) s)
(goops-error "No slot with name `~S' in object ~S" s o))
-
+
(define-method (slot-missing (c <class>) s)
(goops-error "No class slot with name `~S' in class ~S" s c))
-
+
(define-method (slot-missing (c <class>) (o <object>) s value)
(slot-missing c o s))
(define-method (no-applicable-method (gf <generic>) args)
(goops-error "No applicable method for ~S in call ~S"
- gf (cons (generic-function-name gf) args)))
+ gf (cons (generic-function-name gf) args)))
(define-method (no-method (gf <generic>) args)
(goops-error "No method defined for ~S" gf))
;;;
(define-method (shallow-clone (self <object>))
- (let ((clone (%allocate-instance (class-of self) '()))
- (slots (map slot-definition-name
- (class-slots (class-of self)))))
+ (let* ((class (class-of self))
+ (clone (%allocate-instance class))
+ (slots (map slot-definition-name (class-slots class))))
(for-each (lambda (slot)
- (if (slot-bound? self slot)
- (slot-set! clone slot (slot-ref self slot))))
- slots)
+ (when (slot-bound? self slot)
+ (slot-set! clone slot (slot-ref self slot))))
+ slots)
clone))
(define-method (deep-clone (self <object>))
- (let ((clone (%allocate-instance (class-of self) '()))
- (slots (map slot-definition-name
- (class-slots (class-of self)))))
+ (let* ((class (class-of self))
+ (clone (%allocate-instance class))
+ (slots (map slot-definition-name (class-slots class))))
(for-each (lambda (slot)
- (if (slot-bound? self slot)
- (slot-set! clone slot
- (let ((value (slot-ref self slot)))
- (if (instance? value)
- (deep-clone value)
- value)))))
- slots)
+ (when (slot-bound? self slot)
+ (slot-set! clone slot
+ (let ((value (slot-ref self slot)))
+ (if (instance? value)
+ (deep-clone value)
+ value)))))
+ slots)
clone))
;;;
;;; Has correct the following conditions:
;;; Methods
-;;;
+;;;
;;; 1. New accessor specializers refer to new header
-;;;
+;;;
;;; Classes
-;;;
+;;;
;;; 1. New class cpl refers to the new class header
;;; 2. Old class header exists on old super classes direct-subclass lists
;;; 3. New class header exists on new super classes direct-subclass lists
(define-method (class-redefinition (old <class>) (new <class>))
;; Work on direct methods:
- ;; 1. Remove accessor methods from the old class
- ;; 2. Patch the occurences of new in the specializers by old
- ;; 3. Displace the methods from old to new
- (remove-class-accessors! old) ;; -1-
+ ;; 1. Remove accessor methods from the old class
+ ;; 2. Patch the occurences of new in the specializers by old
+ ;; 3. Displace the methods from old to new
+ (remove-class-accessors! old) ;; -1-
(let ((methods (class-direct-methods new)))
(for-each (lambda (m)
- (update-direct-method! m new old)) ;; -2-
+ (update-direct-method! m new old)) ;; -2-
methods)
- (slot-set! new
- 'direct-methods
- (append methods (class-direct-methods old))))
+ (struct-set! new
+ class-index-direct-methods
+ (append methods (class-direct-methods old))))
;; Substitute old for new in new cpl
- (set-car! (slot-ref new 'cpl) old)
-
+ (set-car! (struct-ref new class-index-cpl) old)
+
;; Remove the old class from the direct-subclasses list of its super classes
- (for-each (lambda (c) (slot-set! c 'direct-subclasses
- (delv! old (class-direct-subclasses c))))
- (class-direct-supers old))
+ (for-each (lambda (c) (struct-set! c class-index-direct-subclasses
+ (delv! old (class-direct-subclasses c))))
+ (class-direct-supers old))
;; Replace the new class with the old in the direct-subclasses of the supers
(for-each (lambda (c)
- (slot-set! c 'direct-subclasses
- (cons old (delv! new (class-direct-subclasses c)))))
- (class-direct-supers new))
+ (struct-set! c class-index-direct-subclasses
+ (cons old (delv! new (class-direct-subclasses c)))))
+ (class-direct-supers new))
;; Swap object headers
(%modify-class old new)
;; Now old is NEW!
;; Redefine all the subclasses of old to take into account modification
- (for-each
- (lambda (c)
- (update-direct-subclass! c new old))
- (class-direct-subclasses new))
+ (for-each
+ (lambda (c)
+ (update-direct-subclass! c new old))
+ (class-direct-subclasses new))
;; Invalidate class so that subsequent instances slot accesses invoke
;; change-object-class
- (slot-set! new 'redefined old)
- (%invalidate-class new) ;must come after slot-set!
+ (struct-set! new class-index-redefined old)
+ (class-clear-flags! new vtable-flag-goops-valid) ;must come after slot-set!
old)
(define-method (remove-class-accessors! (c <class>))
(for-each (lambda (m)
-
(if (is-a? m <accessor-method>)
- (let ((gf (slot-ref m 'generic-function)))
- ;; remove the method from its GF
- (slot-set! gf 'methods
- (delq1! m (slot-ref gf 'methods)))
- (invalidate-method-cache! gf)
- ;; remove the method from its specializers
- (remove-method-in-classes! m))))
- (class-direct-methods c)))
+
(when (is-a? m <accessor-method>)
+ (let ((gf (slot-ref m 'generic-function)))
+ ;; remove the method from its GF
+ (slot-set! gf 'methods
+ (delq1! m (slot-ref gf 'methods)))
+ (invalidate-method-cache! gf)
+ ;; remove the method from its specializers
+ (remove-method-in-classes! m))))
+ (class-direct-methods c)))
;;;
;;; update-direct-method!
;;;
(define-method (update-direct-method! (m <method>)
- (old <class>)
- (new <class>))
+ (old <class>)
+ (new <class>))
(let loop ((l (method-specializers m)))
- ;; Note: the <top> in dotted list is never used.
+ ;; Note: the <top> in dotted list is never used.
;; So we can work as if we had only proper lists.
- (if (pair? l)
- (begin
- (if (eqv? (car l) old)
- (set-car! l new))
- (loop (cdr l))))))
+ (when (pair? l)
+ (when (eqv? (car l) old)
+ (set-car! l new))
+ (loop (cdr l)))))
;;;
;;; update-direct-subclass!
;;;
(define-method (update-direct-subclass! (c <class>)
- (old <class>)
- (new <class>))
+ (old <class>)
+ (new <class>))
(class-redefinition c
- (make-class (class-direct-supers c)
- (class-direct-slots c)
- #:name (class-name c)
- #:metaclass (class-of c))))
+ (make-class (class-direct-supers c)
+ (class-direct-slots c)
+ #:name (class-name c)
+ #:metaclass (class-of c))))
;;;
;;; {Utilities for INITIALIZE methods}
;;;
(define (compute-slot-accessors class slots)
(for-each
- (lambda (s g-n-s)
- (let ((getter-function (slot-definition-getter s))
- (setter-function (slot-definition-setter s))
- (accessor (slot-definition-accessor s)))
- (if getter-function
- (add-method! getter-function
- (compute-getter-method class g-n-s)))
- (if setter-function
- (add-method! setter-function
- (compute-setter-method class g-n-s)))
- (if accessor
- (begin
- (add-method! accessor
- (compute-getter-method class g-n-s))
- (add-method! (setter accessor)
- (compute-setter-method class g-n-s))))))
- slots (slot-ref class 'getters-n-setters)))
-
-(define-method (compute-getter-method (class <class>) g-n-s)
- (let ((init-thunk (cadr g-n-s))
- (g-n-s (cddr g-n-s)))
- (make <accessor-method>
- #:specializers (list class)
- #:procedure (cond ((pair? g-n-s)
- (make-generic-bound-check-getter (car g-n-s)))
- (init-thunk
- (standard-get g-n-s))
- (else
- (bound-check-get g-n-s)))
- #:slot-definition g-n-s)))
-
-(define-method (compute-setter-method (class <class>) g-n-s)
- (let ((init-thunk (cadr g-n-s))
- (g-n-s (cddr g-n-s)))
- (make <accessor-method>
- #:specializers (list class <top>)
- #:procedure (if (pair? g-n-s)
- (cadr g-n-s)
- (standard-set g-n-s))
- #:slot-definition g-n-s)))
+ (lambda (slot)
+ (let ((getter (%slot-definition-getter slot))
+ (setter (%slot-definition-setter slot))
+ (accessor-setter setter)
+ (accessor (%slot-definition-accessor slot)))
+ (when getter
+ (add-method! getter (compute-getter-method class slot)))
+ (when setter
+ (add-method! setter (compute-setter-method class slot)))
+ (when accessor
+ (add-method! accessor (compute-getter-method class slot))
+ (add-method! (accessor-setter accessor)
+ (compute-setter-method class slot)))))
+ slots))
+
+(define-method (compute-getter-method (class <class>) slot)
+ (make <accessor-method>
+ #:specializers (list class)
+ #:procedure (slot-definition-slot-ref slot)
+ #:slot-definition slot))
+
+(define-method (compute-setter-method (class <class>) slot)
+ (make <accessor-method>
+ #:specializers (list class <top>)
+ #:procedure (slot-definition-slot-set! slot)
+ #:slot-definition slot))
(define (make-generic-bound-check-getter proc)
- (lambda (o) (assert-bound (proc o) o)))
-
-;; the idea is to compile the index into the procedure, for fastest
-;; lookup.
-
-(eval-when (expand load eval)
- (define num-standard-pre-cache 20))
-
-(define-macro (define-standard-accessor-method form . body)
- (let ((name (caar form))
- (n-var (cadar form))
- (args (cdr form)))
- (define (make-one x)
- (define (body-trans form)
- (cond ((not (pair? form)) form)
- ((eq? (car form) 'struct-ref)
- `(,(car form) ,(cadr form) ,x))
- ((eq? (car form) 'struct-set!)
- `(,(car form) ,(cadr form) ,x ,(cadddr form)))
- (else
- (map body-trans form))))
- `(lambda ,args ,@(map body-trans body)))
- `(define ,name
- (let ((cache (vector ,@(map make-one (iota num-standard-pre-cache)))))
- (lambda (n)
- (if (< n ,num-standard-pre-cache)
- (vector-ref cache n)
- ((lambda (,n-var) (lambda ,args ,@body)) n)))))))
-
-(define-standard-accessor-method ((bound-check-get n) o)
- (let ((x (struct-ref o n)))
- (if (unbound? x)
- (slot-unbound o)
- x)))
-
-(define-standard-accessor-method ((standard-get n) o)
- (struct-ref o n))
-
-(define-standard-accessor-method ((standard-set n) o v)
- (struct-set! o n v))
-
-;;; compute-getters-n-setters
-;;;
-(define (compute-getters-n-setters class slots)
-
- (define (compute-slot-init-function name s)
- (or (let ((thunk (slot-definition-init-thunk s)))
- (and thunk
- (if (thunk? thunk)
- thunk
- (goops-error "Bad init-thunk for slot `~S' in ~S: ~S"
- name class thunk))))
- (let ((init (slot-definition-init-value s)))
- (and (not (unbound? init))
- (lambda () init)))))
-
- (define (verify-accessors slot l)
- (cond ((integer? l))
- ((not (and (list? l) (= (length l) 2)))
- (goops-error "Bad getter and setter for slot `~S' in ~S: ~S"
- slot class l))
- (else
- (let ((get (car l))
- (set (cadr l)))
- (if (not (procedure? get))
- (goops-error "Bad getter closure for slot `~S' in ~S: ~S"
- slot class get))
- (if (not (procedure? set))
- (goops-error "Bad setter closure for slot `~S' in ~S: ~S"
- slot class set))))))
-
- (map (lambda (s)
- ;; The strange treatment of nfields is due to backward compatibility.
- (let* ((index (slot-ref class 'nfields))
- (g-n-s (compute-get-n-set class s))
- (size (- (slot-ref class 'nfields) index))
- (name (slot-definition-name s)))
- ;; NOTE: The following is interdependent with C macros
- ;; defined above goops.c:scm_sys_prep_layout_x.
- ;;
- ;; For simple instance slots, we have the simplest form
- ;; '(name init-function . index)
- ;; For other slots we have
- ;; '(name init-function getter setter . alloc)
- ;; where alloc is:
- ;; '(index size) for instance allocated slots
- ;; '() for other slots
- (verify-accessors name g-n-s)
- (case (slot-definition-allocation s)
- ((#:each-subclass #:class)
- (unless (and (zero? size) (pair? g-n-s))
- (error "Class-allocated slots should not reserve fields"))
- ;; Don't initialize the slot; that's handled when the slot
- ;; is allocated, in compute-get-n-set.
- (cons name (cons #f g-n-s)))
- (else
- (cons name
- (cons (compute-slot-init-function name s)
- (if (or (integer? g-n-s)
- (zero? size))
- g-n-s
- (append g-n-s (list index size)))))))))
- slots))
+ (lambda (o)
+ (let ((val (proc o)))
+ (if (unbound? val)
+ (slot-unbound o)
+ val))))
;;; compute-cpl
;;;
-;;; Correct behaviour:
-;;;
-;;; (define-class food ())
-;;; (define-class fruit (food))
-;;; (define-class spice (food))
-;;; (define-class apple (fruit))
-;;; (define-class cinnamon (spice))
-;;; (define-class pie (apple cinnamon))
-;;; => cpl (pie) = pie apple fruit cinnamon spice food object top
-;;;
-;;; (define-class d ())
-;;; (define-class e ())
-;;; (define-class f ())
-;;; (define-class b (d e))
-;;; (define-class c (e f))
-;;; (define-class a (b c))
-;;; => cpl (a) = a b d c e f object top
-;;;
+
+;; Replace the bootstrap compute-cpl with this definition.
+(define compute-cpl
+ (make <generic> #:name 'compute-cpl))
(define-method (compute-cpl (class <class>))
(compute-std-cpl class class-direct-supers))
-;; Support
-
-(define (only-non-null lst)
- (filter (lambda (l) (not (null? l))) lst))
-
-(define (compute-std-cpl c get-direct-supers)
- (let ((c-direct-supers (get-direct-supers c)))
- (merge-lists (list c)
- (only-non-null (append (map class-precedence-list
- c-direct-supers)
- (list c-direct-supers))))))
-
-(define (merge-lists reversed-partial-result inputs)
- (cond
- ((every null? inputs)
- (reverse! reversed-partial-result))
- (else
- (let* ((candidate (lambda (c)
- (and (not (any (lambda (l)
- (memq c (cdr l)))
- inputs))
- c)))
- (candidate-car (lambda (l)
- (and (not (null? l))
- (candidate (car l)))))
- (next (any candidate-car inputs)))
- (if (not next)
- (goops-error "merge-lists: Inconsistent precedence graph"))
- (let ((remove-next (lambda (l)
- (if (eq? (car l) next)
- (cdr l)
- l))))
- (merge-lists (cons next reversed-partial-result)
- (only-non-null (map remove-next inputs))))))))
-
-;; Modified from TinyClos:
-;;
-;; A simple topological sort.
-;;
-;; It's in this file so that both TinyClos and Objects can use it.
-;;
-;; This is a fairly modified version of code I originally got from Anurag
-;; Mendhekar <anurag@moose.cs.indiana.edu>.
-;;
-
-(define (compute-clos-cpl c get-direct-supers)
- (top-sort ((build-transitive-closure get-direct-supers) c)
- ((build-constraints get-direct-supers) c)
- (std-tie-breaker get-direct-supers)))
-
-
-(define (top-sort elements constraints tie-breaker)
- (let loop ((elements elements)
- (constraints constraints)
- (result '()))
- (if (null? elements)
- result
- (let ((can-go-in-now
- (filter
- (lambda (x)
- (every (lambda (constraint)
- (or (not (eq? (cadr constraint) x))
- (memq (car constraint) result)))
- constraints))
- elements)))
- (if (null? can-go-in-now)
- (goops-error "top-sort: Invalid constraints")
- (let ((choice (if (null? (cdr can-go-in-now))
- (car can-go-in-now)
- (tie-breaker result
- can-go-in-now))))
- (loop
- (filter (lambda (x) (not (eq? x choice)))
- elements)
- constraints
- (append result (list choice)))))))))
-
-(define (std-tie-breaker get-supers)
- (lambda (partial-cpl min-elts)
- (let loop ((pcpl (reverse partial-cpl)))
- (let ((current-elt (car pcpl)))
- (let ((ds-of-ce (get-supers current-elt)))
- (let ((common (filter (lambda (x)
- (memq x ds-of-ce))
- min-elts)))
- (if (null? common)
- (if (null? (cdr pcpl))
- (goops-error "std-tie-breaker: Nothing valid")
- (loop (cdr pcpl)))
- (car common))))))))
-
-
-(define (build-transitive-closure get-follow-ons)
- (lambda (x)
- (let track ((result '())
- (pending (list x)))
- (if (null? pending)
- result
- (let ((next (car pending)))
- (if (memq next result)
- (track result (cdr pending))
- (track (cons next result)
- (append (get-follow-ons next)
- (cdr pending)))))))))
-
-(define (build-constraints get-follow-ons)
- (lambda (x)
- (let loop ((elements ((build-transitive-closure get-follow-ons) x))
- (this-one '())
- (result '()))
- (if (or (null? this-one) (null? (cdr this-one)))
- (if (null? elements)
- result
- (loop (cdr elements)
- (cons (car elements)
- (get-follow-ons (car elements)))
- result))
- (loop elements
- (cdr this-one)
- (cons (list (car this-one) (cadr this-one))
- result))))))
-
;;; compute-get-n-set
;;;
+(define compute-get-n-set
+ (make <generic> #:name 'compute-get-n-set))
+
(define-method (compute-get-n-set (class <class>) s)
(define (class-slot-init-value)
(let ((thunk (slot-definition-init-thunk s)))
(thunk)
(slot-definition-init-value s))))
+ (define (make-closure-variable class value)
+ (list (lambda (o) value)
+ (lambda (o v) (set! value v))))
+
(case (slot-definition-allocation s)
((#:instance) ;; Instance slot
;; get-n-set is just its offset
- (let ((already-allocated (slot-ref class 'nfields)))
- (slot-set! class 'nfields (+ already-allocated 1))
+ (let ((already-allocated (struct-ref class class-index-nfields)))
+ (struct-set! class class-index-nfields (+ already-allocated 1))
already-allocated))
- ((#:class) ;; Class slot
- ;; Class-slots accessors are implemented as 2 closures around
+ ((#:class) ;; Class slot
+ ;; Class-slots accessors are implemented as 2 closures around
;; a Scheme variable. As instance slots, class slots must be
;; unbound at init time.
(let ((name (slot-definition-name s)))
(if (memq name (map slot-definition-name (class-direct-slots class)))
- ;; This slot is direct; create a new shared variable
- (make-closure-variable class (class-slot-init-value))
- ;; Slot is inherited. Find its definition in superclass
- (let loop ((l (cdr (class-precedence-list class))))
- (let ((r (assoc name (slot-ref (car l) 'getters-n-setters))))
- (if r
- (cddr r)
- (loop (cdr l))))))))
+ ;; This slot is direct; create a new shared variable
+ (make-closure-variable class (class-slot-init-value))
+ ;; Slot is inherited. Find its definition in superclass
+ (let lp ((cpl (cdr (class-precedence-list class))))
+ (match cpl
+ ((super . cpl)
+ (let ((s (class-slot-definition super name)))
+ (if s
+ (list (slot-definition-slot-ref s)
+ (slot-definition-slot-set! s))
+ ;; Multiple inheritance means that we might have
+ ;; to look deeper in the CPL.
+ (lp cpl)))))))))
((#:each-subclass) ;; slot shared by instances of direct subclass.
;; (Thomas Buerger, April 1998)
((#:virtual) ;; No allocation
;; slot-ref and slot-set! function must be given by the user
(let ((get (get-keyword #:slot-ref (slot-definition-options s) #f))
- (set (get-keyword #:slot-set! (slot-definition-options s) #f)))
- (if (not (and get set))
- (goops-error "You must supply a #:slot-ref and a #:slot-set! in ~S"
- s))
+ (set (get-keyword #:slot-set! (slot-definition-options s) #f)))
+ (unless (and get set)
+ (goops-error "You must supply a #:slot-ref and a #:slot-set! in ~S" s))
(list get set)))
(else (next-method))))
-(define (make-closure-variable class value)
- (list (lambda (o) value)
- (lambda (o v) (set! value v))))
-
(define-method (compute-get-n-set (o <object>) s)
(goops-error "Allocation \"~S\" is unknown" (slot-definition-allocation s)))
(define-method (compute-slots (class <class>))
- (%compute-slots class))
+ (build-slots-list (class-direct-slots class)
+ (class-precedence-list class)))
;;;
;;; {Initialize}
;;;
+;; FIXME: This could be much more efficient.
+(define (%initialize-object obj initargs)
+ "Initialize the object @var{obj} with the given arguments
+var{initargs}."
+ (define (valid-initargs? initargs)
+ (match initargs
+ (() #t)
+ (((? keyword?) _ . initargs) (valid-initargs? initargs))
+ (_ #f)))
+ (unless (instance? obj)
+ (scm-error 'wrong-type-arg #f "Not an object: ~S"
+ (list obj) #f))
+ (unless (valid-initargs? initargs)
+ (scm-error 'wrong-type-arg #f "Invalid initargs: ~S"
+ (list initargs) #f))
+ (let ((class (class-of obj)))
+ (define (get-initarg kw)
+ (if kw
+ ;; Inlined get-keyword to avoid checking initargs for validity
+ ;; each time.
+ (let lp ((initargs initargs))
+ (match initargs
+ ((kw* val . initargs)
+ (if (eq? kw* kw)
+ val
+ (lp initargs)))
+ (_ *unbound*)))
+ *unbound*))
+ (let lp ((slots (struct-ref class class-index-slots)))
+ (match slots
+ (() obj)
+ ((slot . slots)
+ (define (initialize-slot! value)
+ ((%slot-definition-slot-set! slot) obj value))
+ (let ((initarg (get-initarg (%slot-definition-init-keyword slot))))
+ (cond
+ ((not (unbound? initarg))
+ (initialize-slot! initarg))
+ ((%slot-definition-init-thunk slot)
+ => (lambda (init-thunk)
+ (unless (memq (slot-definition-allocation slot)
+ '(#:class #:each-subclass))
+ (initialize-slot! (init-thunk)))))))
+ (lp slots))))))
+
(define-method (initialize (object <object>) initargs)
(%initialize-object object initargs))
+(define-method (initialize (slot <slot>) initargs)
+ (next-method)
+ (struct-set! slot slot-index-options initargs)
+ (let ((init-thunk (%slot-definition-init-thunk slot)))
+ (when init-thunk
+ (unless (thunk? init-thunk)
+ (goops-error "Bad init-thunk for slot `~S': ~S"
+ (%slot-definition-name slot) init-thunk)))))
+
(define-method (initialize (class <class>) initargs)
+ (define (make-direct-slot-definition dslot)
+ (let ((initargs (compute-direct-slot-definition-initargs class dslot)))
+ (compute-direct-slot-definition class initargs)))
+
(next-method)
- (let ((dslots (get-keyword #:slots initargs '()))
- (supers (get-keyword #:dsupers initargs '())))
- (slot-set! class 'name (get-keyword #:name initargs '???))
- (slot-set! class 'direct-supers supers)
- (slot-set! class 'direct-slots dslots)
- (slot-set! class 'direct-subclasses '())
- (slot-set! class 'direct-methods '())
- (slot-set! class 'cpl (compute-cpl class))
- (slot-set! class 'redefined #f)
- (let ((slots (compute-slots class)))
- (slot-set! class 'slots slots)
- (slot-set! class 'nfields 0)
- (slot-set! class 'getters-n-setters (compute-getters-n-setters class
- slots))
- ;; Build getters - setters - accessors
- (compute-slot-accessors class slots))
-
- ;; Update the "direct-subclasses" of each inherited classes
- (for-each (lambda (x)
- (slot-set! x
- 'direct-subclasses
- (cons class (slot-ref x 'direct-subclasses))))
- supers)
-
- ;; Support for the underlying structs:
-
- ;; Set the layout slot
- (%prep-layout! class)
- ;; Inherit class flags (invisible on scheme level) from supers
- (%inherit-magic! class supers)))
+ (class-add-flags! class (logior vtable-flag-goops-class
+ vtable-flag-goops-valid))
+ (struct-set! class class-index-name (get-keyword #:name initargs '???))
+ (struct-set! class class-index-nfields 0)
+ (struct-set! class class-index-direct-supers
+ (get-keyword #:dsupers initargs '()))
+ (struct-set! class class-index-direct-subclasses '())
+ (struct-set! class class-index-direct-methods '())
+ (struct-set! class class-index-redefined #f)
+ (struct-set! class class-index-cpl (compute-cpl class))
+ (struct-set! class class-index-direct-slots
+ (map (lambda (slot)
+ (if (slot? slot)
+ slot
+ (make-direct-slot-definition slot)))
+ (get-keyword #:slots initargs '())))
+ (struct-set! class class-index-slots
+ (allocate-slots class (compute-slots class)))
+
+ ;; This is a hack.
+ (when (memq <slot> (struct-ref class class-index-cpl))
+ (class-add-flags! class vtable-flag-goops-slot))
+
+ ;; Build getters - setters - accessors
+ (compute-slot-accessors class (struct-ref class class-index-slots))
+
+ ;; Update the "direct-subclasses" of each inherited classes
+ (for-each (lambda (x)
+ (let ((dsubs (struct-ref x class-index-direct-subclasses)))
+ (struct-set! x class-index-direct-subclasses
+ (cons class dsubs))))
+ (struct-ref class class-index-direct-supers))
+
+ ;; Compute struct layout of instances, set the `layout' slot, and
+ ;; update class flags.
+ (%prep-layout! class))
(define (initialize-object-procedure object initargs)
(let ((proc (get-keyword #:procedure initargs #f)))
(cond ((not proc))
- ((pair? proc)
- (apply slot-set! object 'procedure proc))
- (else
+ ((pair? proc)
+ (apply slot-set! object 'procedure proc))
+ (else
(slot-set! object 'procedure proc)))))
(define-method (initialize (applicable-struct <applicable-struct>) initargs)
(next-method)
(initialize-object-procedure applicable-struct initargs))
+(define-method (initialize (applicable-struct <applicable-struct-with-setter>)
+ initargs)
+ (next-method)
+ (slot-set! applicable-struct 'setter (get-keyword #:setter initargs #f)))
+
(define-method (initialize (generic <generic>) initargs)
(let ((previous-definition (get-keyword #:default initargs #f))
- (name (get-keyword #:name initargs #f)))
+ (name (get-keyword #:name initargs #f)))
(next-method)
(slot-set! generic 'methods (if (is-a? previous-definition <procedure>)
- (list (method args
+ (list (method args
(apply previous-definition args)))
- '()))
+ '()))
(if name
- (set-procedure-property! generic 'name name))
- ))
-
-(define-method (initialize (gws <generic-with-setter>) initargs)
- (next-method)
- (%set-object-setter! gws (get-keyword #:setter initargs #f)))
+ (set-procedure-property! generic 'name name))
+ (invalidate-method-cache! generic)))
(define-method (initialize (eg <extended-generic>) initargs)
(next-method)
(slot-set! method 'generic-function (get-keyword #:generic-function initargs #f))
(slot-set! method 'specializers (get-keyword #:specializers initargs '()))
(slot-set! method 'procedure
- (get-keyword #:procedure initargs #f))
+ (get-keyword #:procedure initargs #f))
(slot-set! method 'formals (get-keyword #:formals initargs '()))
(slot-set! method 'body (get-keyword #:body initargs '()))
(slot-set! method 'make-procedure (get-keyword #:make-procedure initargs #f)))
-
+
;;;
;;; {Change-class}
(define (change-object-class old-instance old-class new-class)
(let ((new-instance (allocate-instance new-class '())))
;; Initialize the slots of the new instance
- (for-each (lambda (slot)
- (if (and (slot-exists-using-class? old-class old-instance slot)
- (eq? (slot-definition-allocation
- (class-slot-definition old-class slot))
- #:instance)
- (slot-bound-using-class? old-class old-instance slot))
- ;; Slot was present and allocated in old instance; copy it
- (slot-set-using-class!
- new-class
- new-instance
- slot
- (slot-ref-using-class old-class old-instance slot))
- ;; slot was absent; initialize it with its default value
- (let ((init (slot-init-function new-class slot)))
- (if init
- (slot-set-using-class!
- new-class
- new-instance
- slot
- (apply init '()))))))
- (map slot-definition-name (class-slots new-class)))
+ (for-each
+ (lambda (slot)
+ (if (and (slot-exists? old-instance slot)
+ (eq? (%slot-definition-allocation
+ (class-slot-definition old-class slot))
+ #:instance)
+ (slot-bound? old-instance slot))
+ ;; Slot was present and allocated in old instance; copy it
+ (slot-set! new-instance slot (slot-ref old-instance slot))
+ ;; slot was absent; initialize it with its default value
+ (let ((init (slot-init-function new-class slot)))
+ (when init
+ (slot-set! new-instance slot (init))))))
+ (map slot-definition-name (class-slots new-class)))
;; Exchange old and new instance in place to keep pointers valid
(%modify-instance old-instance new-instance)
;; Allow class specific updates of instances (which now are swapped)
(define-method (update-instance-for-different-class (old-instance <object>)
- (new-instance
- <object>))
+ (new-instance
+ <object>))
;;not really important what we do, we just need a default method
new-instance)
;;;
(define-method (allocate-instance (class <class>) initargs)
- (%allocate-instance class initargs))
+ (%allocate-instance class))
(define-method (make-instance (class <class>) . initargs)
(let ((instance (allocate-instance class initargs)))
;;;
;;; {apply-generic}
;;;
-;;; Protocol for calling standard generic functions. This protocol is
-;;; not used for real <generic> functions (in this case we use a
-;;; completely C hard-coded protocol). Apply-generic is used by
-;;; goops for calls to subclasses of <generic> and <generic-with-setter>.
-;;; The code below is similar to the first MOP described in AMOP. In
-;;; particular, it doesn't used the currified approach to gf
-;;; call. There are 2 reasons for that:
-;;; - the protocol below is exposed to mimic completely the one written in C
-;;; - the currified protocol would be imho inefficient in C.
+;;; Protocol for calling generic functions, intended to be used when
+;;; applying subclasses of <generic> and <generic-with-setter>. The
+;;; code below is similar to the first MOP described in AMOP.
+;;;
+;;; Note that standard generic functions dispatch only on the classes of
+;;; the arguments, and the result of such dispatch can be memoized. The
+;;; `dispatch-generic-function-application-from-cache' routine
+;;; implements this. `apply-generic' isn't called currently; the
+;;; generic function MOP was never fully implemented in GOOPS. However
+;;; now that GOOPS is implemented entirely in Scheme (2015) it's much
+;;; easier to complete this work. Contributions gladly accepted!
+;;; Please read the AMOP first though :)
+;;;
+;;; The protocol is:
+;;;
+;;; + apply-generic (gf args)
+;;; + compute-applicable-methods (gf args ...)
+;;; + sort-applicable-methods (gf methods args)
+;;; + apply-methods (gf methods args)
+;;;
+;;; apply-methods calls make-next-method to build the "continuation" of
+;;; a method. Applying a next-method will call apply-next-method which
+;;; in turn will call apply again to call effectively the following
+;;; method. (This paragraph is out of date but is kept so that maybe it
+;;; illuminates some future hack.)
;;;
(define-method (apply-generic (gf <generic>) args)
- (if (null? (slot-ref gf 'methods))
- (no-method gf args))
+ (when (null? (slot-ref gf 'methods))
+ (no-method gf args))
(let ((methods (compute-applicable-methods gf args)))
(if methods
- (apply-methods gf (sort-applicable-methods gf methods args) args)
- (no-applicable-method gf args))))
+ (apply-methods gf (sort-applicable-methods gf methods args) args)
+ (no-applicable-method gf args))))
;; compute-applicable-methods is bound to %compute-applicable-methods.
-;; *fixme* use let
-(define %%compute-applicable-methods
- (make <generic> #:name 'compute-applicable-methods))
-
-(define-method (%%compute-applicable-methods (gf <generic>) args)
- (%compute-applicable-methods gf args))
-
-(set! compute-applicable-methods %%compute-applicable-methods)
+(define compute-applicable-methods
+ (let ((gf (make <generic> #:name 'compute-applicable-methods)))
+ (add-method! gf (method ((gf <generic>) args)
+ (%compute-applicable-methods gf args)))
+ gf))
(define-method (sort-applicable-methods (gf <generic>) methods args)
- (let ((targs (map class-of args)))
- (sort methods (lambda (m1 m2) (method-more-specific? m1 m2 targs)))))
+ (%sort-applicable-methods methods (map class-of args)))
(define-method (method-more-specific? (m1 <method>) (m2 <method>) targs)
(%method-more-specific? m1 m2 targs))
+(define compute-effective-method
+ (let ((gf (make <generic> #:name 'compute-effective-method)))
+ (add-method! gf (method ((gf <generic>) methods typev)
+ (%compute-effective-method gf methods typev)))
+ gf))
+
+(define compute-specialized-effective-method
+ (let ((gf (make <generic> #:name 'compute-specialized-effective-method)))
+ (add-method!
+ gf
+ (method ((gf <generic>) (method <method>) typev next)
+ (%compute-specialized-effective-method gf method typev next)))
+ gf))
+
+(define-method (compute-specialized-effective-method (gf <generic>)
+ (m <accessor-method>)
+ typev
+ next)
+ (let ((name (slot-definition-name (accessor-method-slot-definition m))))
+ (match typev
+ (#(class)
+ (slot-definition-slot-ref (class-slot-definition class name)))
+ (#(class _)
+ (slot-definition-slot-set! (class-slot-definition class name)))
+ (_
+ (next-method)))))
+
(define-method (apply-method (gf <generic>) methods build-next args)
(apply (method-procedure (car methods))
- (build-next (cdr methods) args)
- args))
+ (build-next (cdr methods) args)
+ args))
(define-method (apply-methods (gf <generic>) (l <list>) args)
(letrec ((next (lambda (procs args)
- (lambda new-args
- (let ((a (if (null? new-args) args new-args)))
- (if (null? procs)
- (no-next-method gf a)
- (apply-method gf procs next a)))))))
+ (lambda new-args
+ (let ((a (if (null? new-args) args new-args)))
+ (if (null? procs)
+ (no-next-method gf a)
+ (apply-method gf procs next a)))))))
(apply-method gf l next args)))
;; We don't want the following procedure to turn up in backtraces:
(for-each (lambda (proc)
- (set-procedure-property! proc 'system-procedure #t))
- (list slot-unbound
- slot-missing
- no-next-method
- no-applicable-method
- no-method
- ))
+ (set-procedure-property! proc 'system-procedure #t))
+ (list slot-unbound
+ slot-missing
+ no-next-method
+ no-applicable-method
+ no-method
+ ))
;;;
-;;; {<composite-metaclass> and <active-metaclass>}
+;;; {Final initialization}
;;;
-;(autoload "active-slot" <active-metaclass>)
-;(autoload "composite-slot" <composite-metaclass>)
-;(export <composite-metaclass> <active-metaclass>)
-
-;;;
-;;; {Tools}
-;;;
+;; Tell C code that the main bulk of Goops has been loaded
+(%goops-loaded)
-;; list2set
-;;
-;; duplicate the standard list->set function but using eq instead of
-;; eqv which really sucks a lot, uselessly here
-;;
-(define (list2set l)
- (let loop ((l l)
- (res '()))
- (cond
- ((null? l) res)
- ((memq (car l) res) (loop (cdr l) res))
- (else (loop (cdr l) (cons (car l) res))))))
-(define (class-subclasses c)
- (letrec ((allsubs (lambda (c)
- (cons c (mapappend allsubs
- (class-direct-subclasses c))))))
- (list2set (cdr (allsubs c)))))
-
-(define (class-methods c)
- (list2set (mapappend class-direct-methods
- (cons c (class-subclasses c)))))
+\f
;;;
-;;; {Final initialization}
+;;; {SMOB and port classes}
;;;
-;; Tell C code that the main bulk of Goops has been loaded
-(%goops-loaded)
+(define <arbiter> (find-subclass <top> '<arbiter>))
+(define <promise> (find-subclass <top> '<promise>))
+(define <thread> (find-subclass <top> '<thread>))
+(define <mutex> (find-subclass <top> '<mutex>))
+(define <condition-variable> (find-subclass <top> '<condition-variable>))
+(define <regexp> (find-subclass <top> '<regexp>))
+(define <hook> (find-subclass <top> '<hook>))
+(define <bitvector> (find-subclass <top> '<bitvector>))
+(define <random-state> (find-subclass <top> '<random-state>))
+(define <async> (find-subclass <top> '<async>))
+(define <directory> (find-subclass <top> '<directory>))
+(define <array> (find-subclass <top> '<array>))
+(define <character-set> (find-subclass <top> '<character-set>))
+(define <dynamic-object> (find-subclass <top> '<dynamic-object>))
+(define <guardian> (find-subclass <applicable> '<guardian>))
+(define <macro> (find-subclass <top> '<macro>))
+
+(define (define-class-subtree class)
+ (define! (class-name class) class)
+ (for-each define-class-subtree (class-direct-subclasses class)))
+
+(define-class-subtree (find-subclass <port> '<file-port>))
HCoop / bpt / guile.git / blobdiff