🚀 go-pugleaf

bcox@gmuvax2.gmu.edu (Brad Cox) writes:
>In article <1992Sep2.045715.5803@panix.com> you write:
>>In <19385@ector.cs.purdue.edu> kane@cs.purdue.edu (Christopher Kane) writes:
>>Although the quoted passage is incorrectly edited, it is usually NOT
>>a good idea to repeat the interface in the implementation.

>The quoted recommendation in our book reflects the voice of pragmatic
>experience, not theoretical necessity. Healthy code is read more than it is
>changed/written. And having to read two files, one for data & procedural
>interfaces and the other for procedural implementations, really is a
>hassle.

When you've taken this step, repeating the instance variable
declarations in the .m file, it comes into your mind that this is
unnecessary redundancy.  What do you need in a  .h  file
additionally to the instance variable and method declarations?

First there is the #import directive for the superclass header
file. If you have all the directories containing the header files
in your cc's -I path then you can extract the directive out of
the class definition:

	@implementation MyObject:Object

in the .m file becomes to

	#import <Object.h>
	@interface MyObject:Object

in the .h file. Next thing are additional typedefs or #defines.
In my early ObjC programs I have used some of them. But as time
went by they showed up as the weak points in my program, where I
couldn't reuse code and design, where the polymorphism was
broken. So I've actually removed all of them. But I've left two
or three #defines for some hardwired implemention restrictions
(oh, blame me:-().

Thus I need a way to write these statements in the .m file. The
easiest solution is the #pragma directive. And because I'm
working with NeXTstep, where  the  header  files  are  in
subdirectories, I use this technique for the superclass header
file too:

	#pragma .h #import <objc/Object.h>
	#pragma .h #define MAXADDRESS 5
	@implementation MyObject:Object

in the .m file becomes to

	#import <objc/Object.h>
	#define MAXADDRESS 5
	@interface MyObject:Object

in the .h file. And I use a simple awk-script to extract the .h
file from the .m file. If you want to see this script then let me
know.

Stefan
-- 
Stefan Krause                          Kiel, Germany
stef@tpki.toppoint.de                  Tel.(voice) +49 431 335022