Hello, Objective-C World!

hello.m

#import <Foundation/Foundation.h>
 
@interface HelloWorld : NSObject
{
}
- (void) sayHello;
@end
 
@implementation HelloWorld
- (void) sayHello
{
    NSLog( @"Hello, Objective-C World!" );
}
 
@end
 
int main( int argc, char* argv[] )
{
    id hw = [HelloWorld alloc];
    [hw sayHello];
    return 0;
}