* Re: [Emacs-diffs] master 35c893d 2/2: Move gensym to core Elisp [not found] ` <20170912151315.C449D2087D@vcs0.savannah.gnu.org> @ 2017-09-12 16:48 ` Stefan Monnier 2017-09-12 17:21 ` Mark Oteiza 0 siblings, 1 reply; 9+ messages in thread From: Stefan Monnier @ 2017-09-12 16:48 UTC (permalink / raw) To: emacs-devel; +Cc: Mark Oteiza > +(defun gensym (&optional prefix) > + "Return a new uninterned symbol. > +The name is made by appending `gensym-counter' to PREFIX. > +PREFIX can be a string, and defaults to \"G\". > +If PREFIX is a number, it replaces the value of `gensym-counter'." I understand that Common-Lisp has that "PREFIX is a number" functionality, but I could never find a use-case for it, so I wonder why we carry over that baggage to Elisp? Stefan ^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [Emacs-diffs] master 35c893d 2/2: Move gensym to core Elisp 2017-09-12 16:48 ` [Emacs-diffs] master 35c893d 2/2: Move gensym to core Elisp Stefan Monnier @ 2017-09-12 17:21 ` Mark Oteiza 2017-09-12 17:35 ` Mark Oteiza 2017-09-12 18:28 ` Stefan Monnier 0 siblings, 2 replies; 9+ messages in thread From: Mark Oteiza @ 2017-09-12 17:21 UTC (permalink / raw) To: Stefan Monnier; +Cc: emacs-devel On 12/09/17 at 12:48pm, Stefan Monnier wrote: > > +(defun gensym (&optional prefix) > > + "Return a new uninterned symbol. > > +The name is made by appending `gensym-counter' to PREFIX. > > +PREFIX can be a string, and defaults to \"G\". > > +If PREFIX is a number, it replaces the value of `gensym-counter'." > > I understand that Common-Lisp has that "PREFIX is a number" > functionality, but I could never find a use-case for it, so I wonder why > we carry over that baggage to Elisp? It was just simpler to not duplicate the code for such a small historical tidbit. I have no problem with the idea of dropping it. ^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [Emacs-diffs] master 35c893d 2/2: Move gensym to core Elisp 2017-09-12 17:21 ` Mark Oteiza @ 2017-09-12 17:35 ` Mark Oteiza 2017-09-12 18:28 ` Stefan Monnier 1 sibling, 0 replies; 9+ messages in thread From: Mark Oteiza @ 2017-09-12 17:35 UTC (permalink / raw) To: Stefan Monnier; +Cc: emacs-devel On 12/09/17 at 01:21pm, Mark Oteiza wrote: > On 12/09/17 at 12:48pm, Stefan Monnier wrote: > > > +(defun gensym (&optional prefix) > > > + "Return a new uninterned symbol. > > > +The name is made by appending `gensym-counter' to PREFIX. > > > +PREFIX can be a string, and defaults to \"G\". > > > +If PREFIX is a number, it replaces the value of `gensym-counter'." > > > > I understand that Common-Lisp has that "PREFIX is a number" > > functionality, but I could never find a use-case for it, so I wonder why > > we carry over that baggage to Elisp? > > It was just simpler to not duplicate the code for such a small > historical tidbit. I have no problem with the idea of dropping it. Is this what you mean? (I lowered the prefix for good measure) diff --git a/doc/lispref/symbols.texi b/doc/lispref/symbols.texi index 2d9ec6fda3..cda5f1c40f 100644 --- a/doc/lispref/symbols.texi +++ b/doc/lispref/symbols.texi @@ -276,8 +276,7 @@ Creating Symbols @defun gensym &optional prefix This function returns a symbol using @code{make-symbol}, whose name is made by appending @code{gensym-counter} to @var{prefix}. The prefix -defaults to @code{"G"}. If @var{prefix} is a number, it replaces the -value of the counter. +defaults to @code{"g"}. @end defun @defun intern name &optional obarray diff --git a/lisp/emacs-lisp/cl-macs.el b/lisp/emacs-lisp/cl-macs.el index eee5953882..3405c92e8d 100644 --- a/lisp/emacs-lisp/cl-macs.el +++ b/lisp/emacs-lisp/cl-macs.el @@ -161,9 +161,16 @@ cl--expr-depends-p ;;; Symbols. -(defvaralias 'cl--gensym-counter 'gensym-counter) +(defvar cl--gensym-counter 0) ;;;###autoload -(cl--defalias 'cl-gensym 'gensym) +(defun cl-gensym (&optional prefix) + "Generate a new uninterned symbol. +The name is made by appending a number to PREFIX, default \"G\"." + (let ((pfix (if (stringp prefix) prefix "G")) + (num (if (integerp prefix) prefix + (prog1 cl--gensym-counter + (setq cl--gensym-counter (1+ cl--gensym-counter)))))) + (make-symbol (format "%s%d" pfix num)))) (defvar cl--gentemp-counter 0) ;;;###autoload diff --git a/lisp/subr.el b/lisp/subr.el index ebb8b53b50..52d4e190e7 100644 --- a/lisp/subr.el +++ b/lisp/subr.el @@ -286,13 +286,10 @@ gensym-counter (defun gensym (&optional prefix) "Return a new uninterned symbol. The name is made by appending `gensym-counter' to PREFIX. -PREFIX can be a string, and defaults to \"G\". -If PREFIX is a number, it replaces the value of `gensym-counter'." - (let ((pfix (if (stringp prefix) prefix "G")) - (num (if (integerp prefix) prefix - (prog1 gensym-counter - (setq gensym-counter (1+ gensym-counter)))))) - (make-symbol (format "%s%d" pfix num)))) +PREFIX is a string, and defaults to \"g\"." + (let ((num (prog1 gensym-counter + (setq gensym-counter (1+ gensym-counter))))) + (make-symbol (format "%s%d" prefix num)))) (defun ignore (&rest _ignore) "Do nothing and return nil. ^ permalink raw reply related [flat|nested] 9+ messages in thread
* Re: [Emacs-diffs] master 35c893d 2/2: Move gensym to core Elisp 2017-09-12 17:21 ` Mark Oteiza 2017-09-12 17:35 ` Mark Oteiza @ 2017-09-12 18:28 ` Stefan Monnier 2017-09-12 18:51 ` Mark Oteiza 2017-09-13 3:48 ` Alex 1 sibling, 2 replies; 9+ messages in thread From: Stefan Monnier @ 2017-09-12 18:28 UTC (permalink / raw) To: Mark Oteiza; +Cc: emacs-devel > It was just simpler to not duplicate the code for such a small > historical tidbit. Damn! So still no explanation for that weird functionality. Stefan ^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [Emacs-diffs] master 35c893d 2/2: Move gensym to core Elisp 2017-09-12 18:28 ` Stefan Monnier @ 2017-09-12 18:51 ` Mark Oteiza 2017-09-13 3:48 ` Alex 1 sibling, 0 replies; 9+ messages in thread From: Mark Oteiza @ 2017-09-12 18:51 UTC (permalink / raw) To: Stefan Monnier; +Cc: emacs-devel On 12/09/17 at 02:28pm, Stefan Monnier wrote: > > It was just simpler to not duplicate the code for such a small > > historical tidbit. > > Damn! So still no explanation for that weird functionality. Nope, the best answer I have is what the CL spec says :( ^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [Emacs-diffs] master 35c893d 2/2: Move gensym to core Elisp 2017-09-12 18:28 ` Stefan Monnier 2017-09-12 18:51 ` Mark Oteiza @ 2017-09-13 3:48 ` Alex 2017-09-13 12:40 ` Stefan Monnier 1 sibling, 1 reply; 9+ messages in thread From: Alex @ 2017-09-13 3:48 UTC (permalink / raw) To: Stefan Monnier; +Cc: Mark Oteiza, emacs-devel Stefan Monnier <monnier@IRO.UMontreal.CA> writes: >> It was just simpler to not duplicate the code for such a small >> historical tidbit. > > Damn! So still no explanation for that weird functionality. > > > Stefan According to [1] (page 53), MACLISP didn't have a visible gensym-counter, and instead used an integer argument to gensym to allow programs to set an internal counter. According to [2], it was only decided in 1989 to have *gensym-counter* in CL, so before then having an integer argument made sense if you wanted to manipulate the gensym state. I don't think an integer argument makes much sense when there's a visible counter available. Checking it only in cl-gensym and not in gensym is a nice idea, but I wonder if people who use an integer argument here are the type of people to use `cl' instead of `cl-lib'. Footnotes: [1] http://www.softwarepreservation.org/projects/LISP/MIT/Moon-MACLISP_Reference_Manual-Apr_08_1974.pdf [2] https://www.cs.cmu.edu/Groups/AI/html/cltl/clm/node110.html ^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [Emacs-diffs] master 35c893d 2/2: Move gensym to core Elisp 2017-09-13 3:48 ` Alex @ 2017-09-13 12:40 ` Stefan Monnier 2017-09-13 12:50 ` Mark Oteiza 0 siblings, 1 reply; 9+ messages in thread From: Stefan Monnier @ 2017-09-13 12:40 UTC (permalink / raw) To: Alex; +Cc: Mark Oteiza, emacs-devel > According to [1] (page 53), MACLISP didn't have a visible > gensym-counter, and instead used an integer argument to gensym to allow > programs to set an internal counter. According to [2], it was only > decided in 1989 to have *gensym-counter* in CL, so before then having an > integer argument made sense if you wanted to manipulate the gensym > state. An integer arg that lets you set the internal counter makes some sense, yes. But the integer arg implements in cl-lib.el (and in clisp, FWIW) does not affect the internal counter. > but I wonder if people who use an integer argument here are the type > of people to use `cl' instead of `cl-lib'. I think using the plural here is rather optimistic. I'd already be surprised if there's even just one user of that functionality. Stefan ^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [Emacs-diffs] master 35c893d 2/2: Move gensym to core Elisp 2017-09-13 12:40 ` Stefan Monnier @ 2017-09-13 12:50 ` Mark Oteiza 2017-09-28 7:05 ` Alex 0 siblings, 1 reply; 9+ messages in thread From: Mark Oteiza @ 2017-09-13 12:50 UTC (permalink / raw) To: Stefan Monnier; +Cc: Alex, emacs-devel On 13/09/17 at 08:40am, Stefan Monnier wrote: > > According to [1] (page 53), MACLISP didn't have a visible > > gensym-counter, and instead used an integer argument to gensym to allow > > programs to set an internal counter. According to [2], it was only > > decided in 1989 to have *gensym-counter* in CL, so before then having an > > integer argument made sense if you wanted to manipulate the gensym > > state. Thanks for digging that up. > > but I wonder if people who use an integer argument here are the type > > of people to use `cl' instead of `cl-lib'. > > I think using the plural here is rather optimistic. I'd already be > surprised if there's even just one user of that functionality. Only one way to find out! I suppose I'll apply the patch I sent earlier. ^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [Emacs-diffs] master 35c893d 2/2: Move gensym to core Elisp 2017-09-13 12:50 ` Mark Oteiza @ 2017-09-28 7:05 ` Alex 0 siblings, 0 replies; 9+ messages in thread From: Alex @ 2017-09-28 7:05 UTC (permalink / raw) To: Mark Oteiza; +Cc: emacs-devel Mark Oteiza <mvoteiza@udel.edu> writes: > On 13/09/17 at 08:40am, Stefan Monnier wrote: >> > According to [1] (page 53), MACLISP didn't have a visible >> > gensym-counter, and instead used an integer argument to gensym to allow >> > programs to set an internal counter. According to [2], it was only >> > decided in 1989 to have *gensym-counter* in CL, so before then having an >> > integer argument made sense if you wanted to manipulate the gensym >> > state. > > Thanks for digging that up. > >> > but I wonder if people who use an integer argument here are the type >> > of people to use `cl' instead of `cl-lib'. >> >> I think using the plural here is rather optimistic. I'd already be >> surprised if there's even just one user of that functionality. > > Only one way to find out! I suppose I'll apply the patch I sent earlier. It doesn't really matter, but wouldn't it be a bit nicer if cl-gensym and gensym shared the same counter and default prefix? ^ permalink raw reply [flat|nested] 9+ messages in thread
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[not found] ` <20170912151315.C449D2087D@vcs0.savannah.gnu.org>
2017-09-12 16:48 ` [Emacs-diffs] master 35c893d 2/2: Move gensym to core Elisp Stefan Monnier
2017-09-12 17:21 ` Mark Oteiza
2017-09-12 17:35 ` Mark Oteiza
2017-09-12 18:28 ` Stefan Monnier
2017-09-12 18:51 ` Mark Oteiza
2017-09-13 3:48 ` Alex
2017-09-13 12:40 ` Stefan Monnier
2017-09-13 12:50 ` Mark Oteiza
2017-09-28 7:05 ` Alex
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