Re: Objective-C Beginner's Guide

[Daniel Boyd]

I think this is a better intro guide:

http://www.gnustep.org/resources/documentation/Developer/Base/ProgrammingManual/manual_1.html

As for why your code isn’t compiling, tough to say without seeing hello.m, but couple thoughts: did you include

 #import <Object.h> 

And in your interface declaration, did you include the “ : Object” at the end: e.g.

@interface Greeter : Object

I haven’t used Object.h (I use Foundation.h as in the example I included). GNUStep objects are typically instantiated with [[obj alloc] init] rather than [obj new]

Sent from my iPhone

On May 31, 2020, at 2:53 PM, Patrick Cardona via Discussion list for the GNUstep programming environment <discuss-gnustep@gnu.org> wrote:

Hi All experienced Objective-C Dev

I begun this Beginner Guide about Objective C :

http://gnustep.made-it.com/BG-objc/

But my beginning is not glorious...

pi@raspberrypi:~/CoursObjectiveC $ ls
hello  hello.m
pi@raspberrypi:~/CoursObjectiveC $ gcc -lobjc hello.m -o hello
hello.m: In function ‘main’:
hello.m:39:2: warning: ‘Greeter’ may not respond to ‘+new’
 myGreeter=[Greeter new];
 ^~~~~~~~~
hello.m:39:2: warning: (Messages without a matching method signature
hello.m:39:2: warning: will be assumed to return ‘id’ and accept
hello.m:39:2: warning: ‘...’ as arguments.)
hello.m:43:2: warning: no ‘-free’ method found
 [myGreeter free];
 ^
pi@raspberrypi:~/CoursObjectiveC $ ./hello
Erreur de segmentation

Is this Beginner's Guide up to date ?

Regards

--
Bien cordialement,
Patrick CARDONA