From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!.POSTED!not-for-mail From: Lars Brinkhoff Newsgroups: gmane.emacs.devel Subject: Re: User-defined record types, v2 Date: Sat, 18 Mar 2017 18:13:08 +0100 Organization: nocrew Message-ID: <86k27mtsnv.fsf@molnjunk.nocrew.org> References: <86y3w2tt2n.fsf@molnjunk.nocrew.org> <86tw6qtt01.fsf@molnjunk.nocrew.org> NNTP-Posting-Host: blaine.gmane.org Mime-Version: 1.0 Content-Type: text/plain X-Trace: blaine.gmane.org 1489857362 9008 195.159.176.226 (18 Mar 2017 17:16:02 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Sat, 18 Mar 2017 17:16:02 +0000 (UTC) User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.3 (gnu/linux) To: emacs-devel@gnu.org Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Sat Mar 18 18:15:58 2017 Return-path: Envelope-to: ged-emacs-devel@m.gmane.org Original-Received: from lists.gnu.org ([208.118.235.17]) by blaine.gmane.org with esmtp (Exim 4.84_2) (envelope-from ) id 1cpHxK-0001PG-9r for ged-emacs-devel@m.gmane.org; Sat, 18 Mar 2017 18:15:54 +0100 Original-Received: from localhost ([::1]:54124 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cpHxQ-00079H-54 for ged-emacs-devel@m.gmane.org; Sat, 18 Mar 2017 13:16:00 -0400 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:55773) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cpHwm-00077V-GZ for emacs-devel@gnu.org; Sat, 18 Mar 2017 13:15:21 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1cpHwi-0001Lz-GO for emacs-devel@gnu.org; Sat, 18 Mar 2017 13:15:20 -0400 Original-Received: from [195.159.176.226] (port=51035 helo=blaine.gmane.org) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1cpHwi-0001Lk-48 for emacs-devel@gnu.org; Sat, 18 Mar 2017 13:15:16 -0400 Original-Received: from list by blaine.gmane.org with local (Exim 4.84_2) (envelope-from ) id 1cpHwV-0004xT-7p for emacs-devel@gnu.org; Sat, 18 Mar 2017 18:15:03 +0100 X-Injected-Via-Gmane: http://gmane.org/ Original-Lines: 226 Original-X-Complaints-To: usenet@blaine.gmane.org Cancel-Lock: sha1:iSHVcYli8VDOtdoPLwHe/ZAk2r0= X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 195.159.176.226 X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Original-Sender: "Emacs-devel" Xref: news.gmane.org gmane.emacs.devel:213133 Archived-At: Update cl-defstruct to use records. * lisp/emacs-lisp/cl-generic.el (cl--generic-struct-tag): Use type-of. (cl--generic-struct-specializers): Adjust to new tag. * lisp/emacs-lisp/cl-macs.el (cl-defstruct): Use type=nil as before. Use the type symbol as the tag. Use copy-record to copy structs. (cl--defstruct-predicate): New function. (cl--pcase-mutually-exclusive-p): Use it. (cl-struct-sequence-type): Can now return `record'. * lisp/emacs-lisp/cl-preloaded.el (cl--make-slot-desc): Adjust ad-hoc code to new format. (cl--struct-register-child): Work with records. (cl-struct-define): Don't touch the tag's symbol-value and symbol-function slots when we use the type as tag. diff --git a/lisp/emacs-lisp/cl-generic.el b/lisp/emacs-lisp/cl-generic.el index 8c6d3d5..e15c942 100644 --- a/lisp/emacs-lisp/cl-generic.el +++ b/lisp/emacs-lisp/cl-generic.el @@ -1082,24 +1082,8 @@ cl--generic-eql-used ;;; Support for cl-defstructs specializers. (defun cl--generic-struct-tag (name &rest _) - ;; It's tempting to use (and (vectorp ,name) (aref ,name 0)) - ;; but that would suffer from some problems: - ;; - the vector may have size 0. - ;; - when called on an actual vector (rather than an object), we'd - ;; end up returning an arbitrary value, possibly colliding with - ;; other tagcode's values. - ;; - it can also result in returning all kinds of irrelevant - ;; values which would end up filling up the method-cache with - ;; lots of irrelevant/redundant entries. - ;; FIXME: We could speed this up by introducing a dedicated - ;; vector type at the C level, so we could do something like - ;; (and (vector-objectp ,name) (aref ,name 0)) - `(and (vectorp ,name) - (> (length ,name) 0) - (let ((tag (aref ,name 0))) - (and (symbolp tag) - (eq (symbol-function tag) :quick-object-witness-check) - tag)))) + ;; Use exactly the same code as for `typeof'. + `(if ,name (type-of ,name) 'null)) (defun cl--generic-class-parents (class) (let ((parents ()) @@ -1113,8 +1097,8 @@ cl--generic-class-parents (nreverse parents))) (defun cl--generic-struct-specializers (tag &rest _) - (and (symbolp tag) (boundp tag) - (let ((class (symbol-value tag))) + (and (symbolp tag) + (let ((class (get tag 'cl--class))) (when (cl-typep class 'cl-structure-class) (cl--generic-class-parents class))))) diff --git a/lisp/emacs-lisp/cl-macs.el b/lisp/emacs-lisp/cl-macs.el index 40342f3..7e08ca2 100644 --- a/lisp/emacs-lisp/cl-macs.el +++ b/lisp/emacs-lisp/cl-macs.el @@ -2604,11 +2604,24 @@ cl-defstruct (print-func nil) (print-auto nil) (safety (if (cl--compiling-file) cl--optimize-safety 3)) (include nil) - (tag (intern (format "cl-struct-%s" name))) + ;; There are 4 types of structs: + ;; - `vector' type: means we should use a vector, which can come + ;; with or without a tag `name', which is usually in slot 0 + ;; but obeys :initial-offset. + ;; - `list' type: same as `vector' but using lists. + ;; - `record' type: means we should use a record, which necessarily + ;; comes tagged in slot 0. Currently we'll use the `name' as + ;; the tag, but we may want to change it so that the class object + ;; is used as the tag. + ;; - nil type: this is the "pre-record default", which uses a vector + ;; with a tag in slot 0 which is a symbol of the form + ;; `cl-struct-NAME'. We need to still support this for backward + ;; compatibility with old .elc files. + (tag name) (tag-symbol (intern (format "cl-struct-%s-tags" name))) (include-descs nil) (include-name nil) - (type nil) + (type nil) ;nil here means not specified explicitly. (named nil) (forms nil) (docstring (if (stringp (car descs)) (pop descs))) @@ -2648,7 +2661,9 @@ cl-defstruct ((eq opt :print-function) (setq print-func (car args))) ((eq opt :type) - (setq type (car args))) + (setq type (car args)) + (unless (memq type '(vector list)) + (error "Invalid :type specifier: %s" type))) ((eq opt :named) (setq named t)) ((eq opt :initial-offset) @@ -2680,13 +2695,11 @@ cl-defstruct (pop include-descs))) (setq descs (append old-descs (delq (assq 'cl-tag-slot descs) descs)) type inc-type - named (if type (assq 'cl-tag-slot descs) 'true)) - (if (cl--struct-class-named include) (setq tag name named t))) - (if type - (progn - (or (memq type '(vector list)) - (error "Invalid :type specifier: %s" type)) - (if named (setq tag name))) + named (if (memq type '(vector list)) + (assq 'cl-tag-slot descs) + 'true)) + (if (cl--struct-class-named include) (setq named t))) + (unless type (setq named 'true))) (or named (setq descs (delq (assq 'cl-tag-slot descs) descs))) (when (and (null predicate) named) @@ -2696,7 +2709,9 @@ cl-defstruct (length (memq (assq 'cl-tag-slot descs) descs))))) (cond - ((memq type '(nil vector)) + ((null type) ;Record type. + `(memq (type-of cl-x) ,tag-symbol)) + ((eq type 'vector) `(and (vectorp cl-x) (>= (length cl-x) ,(length descs)) (memq (aref cl-x ,pos) ,tag-symbol))) @@ -2793,7 +2808,9 @@ cl-defstruct (setq slots (nreverse slots) defaults (nreverse defaults)) (and copier - (push `(defalias ',copier #'copy-sequence) forms)) + (push `(defalias ',copier + ,(if (null type) '#'copy-record '#'copy-sequence)) + forms)) (if constructor (push (list constructor (cons '&key (delq nil (copy-sequence slots)))) @@ -2808,7 +2825,7 @@ cl-defstruct (format "Constructor for objects of type `%s'." name)) ,@(if (cl--safe-expr-p `(progn ,@(mapcar #'cl-second descs))) '((declare (side-effect-free t)))) - (,(or type #'vector) ,@make)) + (,(or type #'record) ,@make)) forms))) (if print-auto (nconc print-func (list '(princ ")" cl-s) t))) ;; Don't bother adding to cl-custom-print-functions since it's not used @@ -2866,6 +2883,15 @@ cl--struct-all-parents ,pat))) fields))) +(defun cl--defstruct-predicate (type) + (let ((cons (assq (cl-struct-sequence-type type) + `((list . consp) + (vector . vectorp) + (nil . recordp))))) + (if cons + (cdr cons) + 'recordp))) + (defun cl--pcase-mutually-exclusive-p (orig pred1 pred2) "Extra special cases for `cl-typep' predicates." (let* ((x1 pred1) (x2 pred2) @@ -2888,14 +2914,12 @@ cl--pcase-mutually-exclusive-p (memq c2 (cl--struct-all-parents c1))))))) (let ((c1 (and (symbolp t1) (cl--find-class t1)))) (and c1 (cl--struct-class-p c1) - (funcall orig (if (eq 'list (cl-struct-sequence-type t1)) - 'consp 'vectorp) + (funcall orig (cl--defstruct-predicate t1) pred2))) (let ((c2 (and (symbolp t2) (cl--find-class t2)))) (and c2 (cl--struct-class-p c2) (funcall orig pred1 - (if (eq 'list (cl-struct-sequence-type t2)) - 'consp 'vectorp)))) + (cl--defstruct-predicate t2)))) (funcall orig pred1 pred2)))) (advice-add 'pcase--mutually-exclusive-p :around #'cl--pcase-mutually-exclusive-p) @@ -2903,8 +2927,8 @@ cl--pcase-mutually-exclusive-p (defun cl-struct-sequence-type (struct-type) "Return the sequence used to build STRUCT-TYPE. -STRUCT-TYPE is a symbol naming a struct type. Return `vector' or -`list', or nil if STRUCT-TYPE is not a struct type. " +STRUCT-TYPE is a symbol naming a struct type. Return `record', +`vector`, or `list' if STRUCT-TYPE is a struct type, nil otherwise." (declare (side-effect-free t) (pure t)) (cl--struct-class-type (cl--struct-get-class struct-type))) diff --git a/lisp/emacs-lisp/cl-preloaded.el b/lisp/emacs-lisp/cl-preloaded.el index bba7b83..bd77654 100644 --- a/lisp/emacs-lisp/cl-preloaded.el +++ b/lisp/emacs-lisp/cl-preloaded.el @@ -64,7 +64,7 @@ cl-struct-cl-structure-object-tags ;; cl--slot-descriptor. ;; BEWARE: Obviously, it's important to keep the two in sync! (lambda (name &optional initform type props) - (vector 'cl-struct-cl-slot-descriptor + (record 'cl-slot-descriptor name initform type props))) (defun cl--struct-get-class (name) @@ -101,7 +101,7 @@ cl--plist-remove (defun cl--struct-register-child (parent tag) ;; Can't use (cl-typep parent 'cl-structure-class) at this stage ;; because `cl-structure-class' is defined later. - (while (vectorp parent) + (while (recordp parent) (add-to-list (cl--struct-class-children-sym parent) tag) ;; Only register ourselves as a child of the leftmost parent since structs ;; can only only have one parent. @@ -150,7 +150,7 @@ cl-struct-define parent name)))) (add-to-list 'current-load-list `(define-type . ,name)) (cl--struct-register-child parent-class tag) - (unless (eq named t) + (unless (or (eq named t) (eq tag name)) ;; We used to use `defconst' instead of `set' but that ;; has a side-effect of purecopying during the dump, so that the ;; class object stored in the tag ends up being a *copy* of the