Inheritence!

[Arcadiu]

Sorry, I have had a break from Objective C so I am going through this book making practice code because the book fails to put in exercises.

I have become frustrated as I am not able to get the class Second to inherit from the class first!

I also get a warning on [second print] saying second may not respont to -print and another warning on Second *second = [[Second alloc] init];
saying Second may not respond to +alloc

Finally, my actual error says it cannot find interface decleration for 'First', superclass of 'Second'.

This is my code and I would be really grateful if someone could point out the error.

#import <Foundation/Foundation.h>

@interface Second : First
{
}
@end

@implementation Second
@end




////////////////////////////////////////////////////////////////////////////////////
@interface First : NSObject
{
	
}
-(void) print;

@end

@implementation First

-(void) print 
{
	NSLog(@"Test");
}

@end

////////////////////////////////////////////////////////////////////////////////////

int main (){
	
	First *first = [[First alloc] init];
	Second *second = [[Second alloc] init];
	[second print];
	[first print];
	return 0;
}

[Nanyko]

Files are parsed top to bottom. At the point where you declared the interface of the 'Second' class, the compiler doesn't yet know a 'First' class exists because you declared it further down. Try declaring the 'First' class first, and then the 'Second' one.

[Arcadiu]

wow! never knew that! thankyou very much!