mirror of
https://git.savannah.gnu.org/git/emacs.git
synced 2024-11-26 07:33:47 +00:00
124 lines
4.2 KiB
Plaintext
124 lines
4.2 KiB
Plaintext
NS -- the Cocoa interface for macOS and compatible systems
|
||
----------------------------------------------------------
|
||
|
||
This directory contains files needed to build Emacs on system based on
|
||
NextStep (NS), including macOS and GNUstep, using the Cocoa API.
|
||
|
||
|
||
HISTORY
|
||
|
||
|
||
The Nextstep (NS) interface of GNU Emacs was originally written in
|
||
1994 for NeXTSTEP systems running Emacs 19 and subsequently ported to
|
||
OpenStep and then Rhapsody, which became Mac OS X. In 2004 it was
|
||
adapted to GNUstep, a free OpenStep implementation, and in 2008 it was
|
||
merged to the GNU Emacs trunk and released with Emacs 23. Around the
|
||
same time a separate Mac-only port using the Carbon APIs and
|
||
descending from a 2001 Mac OS 8/9 port of Emacs 21 was removed. (It
|
||
remains available externally under the name "mac".)
|
||
|
||
|
||
OVERVIEW OF COCOA AND OBJECTIVE-C
|
||
|
||
Cocoa is an API for the Objective-C language, an objective oriented
|
||
superset of C. Anybody with experience with iOS or modern macOS
|
||
application development should feel at home.
|
||
|
||
A method call in Objective-C differs from most other languages in the
|
||
fact that it doesn't have a normal name. Instead, the method name is
|
||
made up of the name of each parameter. An exception to this rule are
|
||
methods without parameters.
|
||
|
||
The following calls a method in the object 'anObject'.
|
||
|
||
[anObject alpha:1 beta:2 gamma:3];
|
||
|
||
Classes are declared like the following:
|
||
|
||
@interface AClassName
|
||
{
|
||
// A class method.
|
||
+ (TYPE)name1:(TYPE)param1
|
||
|
||
// An object method.
|
||
- (TYPE)name1:(TYPE)param1 name2:(TYPE)param2;
|
||
}
|
||
@end
|
||
|
||
|
||
GUIDELINES
|
||
|
||
* Adhere the to the FSF philosophy that a feature in GNU software
|
||
should not only be available on non-free systems.
|
||
|
||
* People with varying Cocoa and Objective-C skills will read and
|
||
modify the NS code over a long period of time. Keep the code simple
|
||
and avoid language constructs that makes the code hard to maintain.
|
||
|
||
* Don't use macros and types intended for the XCode Interface Builder,
|
||
like 'IBAction'.
|
||
|
||
* The NS interface should work on all version of macOS from Mac OS X
|
||
10.6.8 (Snow Leopard) to the latest official release.
|
||
|
||
* Under macOS, it is possible to build Emacs using NS, X11, or console
|
||
only. A new macOS feature should work in all appropriate builds.
|
||
|
||
|
||
TRACING SUPPORT
|
||
|
||
The NS interface features a printf-based trace package that prints the
|
||
call tree of selected functions in the Cocoa interface, plus various
|
||
extra information. It can be enabled by uncommenting the line
|
||
defining 'NSTRACE_ENABLED' in "nsterm.h". To enable more output,
|
||
uncomment the lines defining symbols starting with 'NSTRACE_GROUP'.
|
||
|
||
|
||
GNUSTEP AND OTHER COMPATIBLE SYSTEMS
|
||
|
||
The NS interface works on systems compatible with macOS, for example
|
||
GNUstep. Even though they are less frequently used, this is important
|
||
for a number of reasons:
|
||
|
||
* It supports the GNUstep project and provides an Emacs with the same
|
||
look-and-feel as the rest of the system.
|
||
|
||
* This allows other Emacs developers to test their changes on the NS
|
||
interface without having access to a macOS machine.
|
||
|
||
* If a feature in the NS interface work on free systems like GNUstep,
|
||
this meets the FSF requirement that features in GNU software should
|
||
not only be available on non-free systems.
|
||
|
||
|
||
SEE ALSO
|
||
|
||
The src/ns... files contains the C and Objective-C parts.
|
||
|
||
The lisp/term/ns-win.el file contains the lisp part of the NS
|
||
interface.
|
||
|
||
The INSTALL file in this directory for compilation instructions.
|
||
|
||
The Nextstep section in the etc/TODO file for a list of ideas for
|
||
future development.
|
||
|
||
|
||
----------------------------------------------------------------------
|
||
Copyright 2008-2021 Free Software Foundation, Inc.
|
||
|
||
This file is part of GNU Emacs.
|
||
|
||
GNU Emacs is free software: you can redistribute it and/or modify
|
||
it under the terms of the GNU General Public License as published by
|
||
the Free Software Foundation, either version 3 of the License, or
|
||
(at your option) any later version.
|
||
|
||
GNU Emacs is distributed in the hope that it will be useful,
|
||
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||
GNU General Public License for more details.
|
||
|
||
You should have received a copy of the GNU General Public License
|
||
along with GNU Emacs. If not, see <https://www.gnu.org/licenses/>.
|