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diff --git a/doc/lispref/anti.texi b/doc/lispref/anti.texi index ced8082f6a4..118df05c791 100644 --- a/doc/lispref/anti.texi +++ b/doc/lispref/anti.texi @@ -6,186 +6,179 @@ @c This node must have no pointers. @node Antinews -@appendix Emacs 26 Antinews +@appendix Emacs 27 Antinews @c Update the elisp.texi Antinews menu entry with the above version number. For those users who live backwards in time, here is information about -downgrading to Emacs version 26.3. We hope you will enjoy the greater +downgrading to Emacs version 27.2. We hope you will enjoy the greater simplicity that results from the absence of many @w{Emacs @value{EMACSVER}} features. @itemize @bullet @item -Lisp objects are again implemented on the C level as integer types, -not as pointers. This might be a small step for Emacs Lisp users, but -it's a giant leap for the Emacs developers who work on the C level, -since it is now again easy to print Lisp object in the debugger in the -decimal format, which is so much easier for debugging. It also makes -calling Emacs functions from the debugger easier, and allows us to -freely mix integers and Lisp objects in the C code. +The annoying @code{lexical-binding} local variable now heeds the +value of @code{enable-local-variables}: if it's @code{nil}, the +@code{lexical-binding} cookie is ignored. We are working hard on +removing the lexical-binding support in some past Emacs version, and +this small step advances us back to that change. @item -The test suite was removed from the distribution tarball. We believe -that tests need seldom if ever be run, certainly not by the end -users. Removing the tests from the tarball makes it much smaller, -which is important since disk space becomes more and more at premium -as you move back in time. +The @code{load-dangerous-libraries} variable is not obsolete, as it +must be used to allow loading Lisp compiled by XEmacs, which will +become more and more important as you move back in time. @item -Dynamic module support is disabled by default. This both makes Emacs -smaller (a worthy goal by itself), and removes the complications and -additional complexity related with installing module support files and -letting random shared objects an opportunity to be loaded into Emacs -and mess with it. +The optional @var{modes} argument of @code{interactive} is not +supported, and every command is deemed applicable to any major mode. +We believe this makes the life of Lisp programmers much simpler, as +there's now no need to tag commands with the modes where they make +sense. @item -You now must activate any installed packages only after loading your -init files. That requires an explicit call to -@code{package-initialize} in your init file, which is a Good Thing, as -it makes you think seriously where and indeed whether you'd like your -packages to become available to your sessions. Simplicity should -tramp convenience! +Shorthands for Lisp symbols have been removed, which makes loading +Lisp files and handling Lisp symbols much simpler and more efficient. +This is important for decent performance on slower CPUs as you move +back in time. @item To reduce the amount of code in Emacs related to unimportant features, -we've removed native rotation and resizing of images. You will have -to build Emacs with ImageMagick if you want to resize or rotate images -inside Emacs. We don't expect anyone to miss that. +we've removed the variables @code{global-minor-modes} and +@code{local-minor-modes}. If your Lisp program needs to determine +whether some minor mode is in effect, it will have to test explicitly +for every mode. We don't expect anyone to miss those fancy variables. @item -We've re-enabled color fonts usage by the XFT font back-end. We -consider the availability of these fonts more important than a random -crash here and there, especially since the use of these fonts for -displaying Emoji will become less and less important as we travel back -in time, and will completely disappear in some past Emacs version. +The default preference for servicing sub-processes that produce output +at a high rate, and the associated variable +@code{process-prioritize-lower-fds}, have been removed. Moving back +in time means fewer and fewer programs can produce such high-rate +output, so this features becomes just useless crud. @item -The function @code{network-interface-list} can now return only IPv4 -addresses. We consider the complexity introduced by IPv6 to be too -much to be justified, and on the other hand its removal is the step in -the right direction, given that IPv6 is expected to be completely -removed as we move back in time. +The encodings that are variants of EBCDIC were removed. This includes +@code{ibm256}, @code{ibm273}, and others---variants of the EBCDIC +encoding tailored for some Japanese and European locales. You won't +need those where you are going. @item -The limit on repetitions in regular expressions was reduced to -@ifnottex -2**15 @minus{} 1. -@end ifnottex -@tex -@math{2^{15}-1}. -@end tex -We envision that regular expressions will become more and more simple -as we move towards the distant past. +The ``Bindat type expression'' description language has been removed, +as the existing data layout specifications are perfectly suited for +this job. @item To simplify code and reduce complexity, we removed the capability of -searching programs on remote hosts in @code{executable-find}. If you -really need this feature (why would you?), you can always write your -own shell script and run it on the remote. +specifying the success handler in @code{condition-case} via the +@code{:success} keyword. If you really need this feature (why would +you?), you can always write some simple Lisp that has the same effect. @item -The @code{:extend} face attribute is no longer available; all faces -have their background color extended by default past end of line. -This should significantly simplify face management and remove -unnecessary code bloat, as well as make faces significantly simpler to -understand and use. +Emacs modules can no longer provide interactive functions, or install +finalizers, nor open channels to existing pipe sub-processes. All +this is extra ballast, especially since we plan on removing modules in +some past Emacs version. The @code{make_unibyte_string} module API +was removed for the same reason. @item -The predicates @code{display-blink-cursor-p} and -@code{display-symbol-keys-p} were deleted. They are rarely if ever -needed, and can easily be substituted by appropriate calls to old and -proven APIs like @code{display-graphic-p}. As an additional bonus, -writing Lisp programs that depend on this functionality will make sure -the programmer understands better what exactly is the required -features of the display terminal. +To keep Emacs clean and elegant, we've removed the +@code{print-integers-as-characters} option. Recognizing characters by +their decimal codes is a basic requirement for Emacs Lisp programmers, +and with the expected decrease in use of Unicode characters, this will +be soon limited to ASCII only: surely something you all can master! @item -Relative directories in the value of the @env{HOME} environment -variable are once again interpreted relative to the -@code{default-directory} of the current buffer. This is much simpler, -and also allows @env{HOME} to resolve to a different place in -different buffers, which allows some interesting applications. +The optional @var{count} argument of the @code{directory-files} +function has been removed. Extracting the first @var{n} members from +the full list is trivial, so this is a significant simplification for +an insignificant cost. -For the same reasons, @code{file-name-absolute-p} now again considers -@file{~foo} an absolute file name, even if there's no known user -@samp{foo}. This means a Lisp program which uses such file names will -always work the same on any system, regardless of its known users. +@item +Functions that create sub-processes and network connections no longer +accept the @code{:coding} argument; use +@code{set-process-coding-system} or bind +@code{coding-system-for-read/write} instead: again, a significant +reduction in Emacs complexity for little or no cost. + +@item +We deleted from the macros @code{define-derived-mode} and +@code{define-minor-mode} the code which allowed using the +@code{:interactive} argument. The possibility of marking a mode +non-interactive makes very little sense, + +@item +The possibility of having links to man pages in doc strings has been +removed. Use plain text instead, if you need such references. + +@item +Temporary buffers are no longer exempt from running any buffer-related +hooks. Programs that don't want such hooks in some buffer can always +disable it locally, whereas making that simpler complicates Emacs for +no good reason. @item -File-related primitives like @code{file-attributes}, -@code{file-modes}, @code{file-newer-than-file-p}, and some others once -again return @code{nil} when the underlying low-level APIs fail, -instead of signaling an error. We decided that functions which signal -errors require more complex code from Lisp programs which use them, -and found this complexity unjustified when returning @code{nil} will -do. +Several features that complicated the byte compiler have been removed: +@itemize @minus @item -Similarly, old-style backquotes no longer signal errors; they generate -warnings instead. You can remove error handling from programs that -use backquotes. +The checks for missing declarations of dynamic variables. This will +continue making less and less sense as we move away of lexical-binding +support. @item -Formatting floating-point numbers has been sped up by letting the -underlying implementation produce unpredictable values, instead of -signaling errors when the number is too large to format correctly. We -believe the Emacs Lisp programmers should always know what they are -doing when they deal with floating-point values. +The ability of compiling symlinked @file{*.el} files, which is really +gross: copy the files instead. @item -The function @code{read-char-from-minibuffer} was deleted. We decided -that @code{read-char} should be enough for any Lisp program that needs -to ask the user for a single-character input, in recognition of the -fact that nothing makes Emacs Lisp hackers rejoice more than the need -to sit down and write yet another interactive question-and-answer -function, and make it optimal for each specific case. Consequently, -no history is provided for such responses (why would someone want -history of single-key strokes, anyway?). +The warnings about too-wide doc strings---that is just a nuisance, as +the programmers should be trusted to know what they are doing. +@end itemize + + +@item +We deleted several features of the @code{pcase} macro, in accordance +with our general plane to remove @code{pcase} from Emacs: +@itemize @minus @item -The function @code{ngettext} was deleted. Non-English languages will -become less and less widespread, let alone useful, as you move back in -time, so we took this small step in that direction, and simplified -Emacs as a nice bonus. +The @code{cl-type} pattern. @item -Focus-change notifications on text-mode frames are no longer -recognized or supported. You can now safely disregard the possibility -of receiving such notifications on TTY frames. This is one small step -on the long road of removing all non-character input events Emacs -supports on TTY frames. +the @code{pcase-setq} macro. + +@item +The @code{pcase-compile-patterns} function. +@end itemize @item -Face specifications in @code{face-remapping-alist} now have to be -buffer-specific, without any differences between windows showing the -same buffers. This allowed us to remove a lot of unneeded code bloat -from Emacs, and make the face handling much simpler. +Some of the keywords used in Edebug specification lists were deemed to +be of little use, and were therefore removed: @code{&interpose}, +@code{&error}, and @code{&name}. The long-term plane is for Emacs to +drop Edebug entirely, leaving only the trusted Lisp debugger, and we +continue working according to that plan. @item -The @samp{%o} and @samp{%x} formats now always produce unsigned -values, as you'd expect. This allows you to reveal the underlying -machine representation, which is different on each architecture, -something we consider a valuable feature. +The function @code{object-intervals} was dropped, as a Lisp program +can easily collect the intervals of a buffer or a string by iterating +through them one by one. @item -We no longer highlight in @code{font-lock-warning-face} symbols with -confusable quote characters, such as U+2018. Detecting them -needed non-trivial amount of code, and we firmly believe that Lisp -programmers always know what they are doing, and don't need to be -annoyed with typefaces that stand out and distract. +We decided that the @code{require-theme} function is an unnecessary +complication, so we deleted it. Lisp programs can easily search along +@code{custom-theme-load-path} instead. @item -The function @code{file-system-info} was dropped on Posix platforms, -since you can always invoke @command{df} instead and parse its -output. +The convenience functions @code{length<}, @code{length>}, and +@code{length=} were removed, as using @code{length} followed by a +comparison should be good enough for everyone, especially considering +that the typical length of a list keeps going down as you move back +through time. @item -The functions that implement the @samp{base64url} encoding were -removed, as they can always be emulated by suitable tweaking of the -normal base-64 encoding. No need to bloat Emacs and force Lisp -programmers learn more interfaces on this account. +The variable @code{current-minibuffer-command} is no longer available, +as we found little justification for keeping it. @item As part of the ongoing quest for simplicity, many other functions and -variables have been eliminated. +variables have been eliminated. Other functions and variables, that +were declared obsolete since Emacs 23, have been added back, in +preparation for releasing Emacs 23 in some distant past. @end itemize |