macOS dealloc undeclared

[jamesapp]

james-collinss-macbook-prorog15 jamescollins$ gcc -framework Foundation AddressBook.m prog15.11.m -o prog15.11
AddressBook.m: In function ‘-[AddressBook initWithName:]’:
AddressBook.m:8: warning: conflicting types for ‘-(id)initWithNameNSString *)name’
AddressBook.h:11: warning: previous declaration of ‘-(AddressBook *)initWithNameNSString *)name’
AddressBook.m: In function ‘-[AddressBook list]’:
AddressBook.m:34: warning: ‘cString’ is deprecated (declared at /System/Library/Frameworks/Foundation.framework/Headers/NSString.h:345)
AddressBook.m:39: warning: ‘cString’ is deprecated (declared at /System/Library/Frameworks/Foundation.framework/Headers/NSString.h:345)
AddressBook.m:40: warning: ‘cString’ is deprecated (declared at /System/Library/Frameworks/Foundation.framework/Headers/NSString.h:345)
AddressBook.m:48: error: ‘dealloc’ undeclared (first use in this function)
AddressBook.m:48: error: (Each undeclared identifier is reported only once
AddressBook.m:48: error: for each function it appears in.)
AddressBook.m:48: error: syntax error before ‘{’ token
AddressBook.m: At top level:
AddressBook.m:53: warning: incomplete implementation of class ‘AddressBook’
AddressBook.m:53: warning: method definition for ‘-dealloc’ not found

got these error messages when i tried to compile a program from a book on Objective-C.

-i was told cString is no longer used, so i understand that warning message.
the thing that i don't understand is AddressBook.m:48 error: 'dealloc' undeclared (first use in this function)...
i have in my interface file

-(void) dealloc;

i will include the interface file which i called AddressBook.h

#import <Foundation/NSArray.h>
#import <stdio.h>
#import "AddressCard.h"

@interface AddressBook: NSObject
{
  NSString       *bookName;
  NSMutableArray *book;
}

-(AddressBook *) initWithName: (NSString *) name;
-(void) addCard: (AddressCard *) theCard;
-(int) entries;
-(void) list;
-(void) dealloc;

@end

and my implementation file which i called AddressBook.m

#import "AddressBook.h"

@implementation AddressBook;

// set up the AddressBook's name and an empty book

-(id) initWithName: (NSString *) name
{
  self = [super init];
  if (self) {
    bookName = [[NSString alloc] initWithString: name];
    book = [[NSMutableArray alloc] init];
    }
    
  return self;
}

-(void) addCard: (AddressCard *) theCard
{
  [book addObject: theCard];
}

-(int) entries
{
  return [book count];
}

-(void) list
{
  int     i, elements;
  AddressCard *theCard;
  
  printf ("\n======== Contents of: %s =========\n",
           [bookName cString]);
  elements = [book count];
  
  for ( i = 0; i < elements; ++i ) {
      theCard = [book objectAtIndex: i];
      printf ("%-20s %-32s\n", [[theCard name] cString],
                   [[theCard email] cString]);
  }
  
  printf("========================================\
          ============\n\n");
  
          
-(void) dealloc
{
  [bookName release];
  [book release];
  [super dealloc];
}
@end

and my test file which i called prog15.11.m

#import "AddressBook.h"
#import <Foundation/NSAutoreleasePool.h>

int main (int argc, char *argv[])
{
  NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
  
  NSString *aName = @"Julia Kochan";
  NSString *aEmail = @"jewls337@axlc.com";
  NSString *bName = @"Tony Iannino";
  NSString *bEmail = @"tony.iannino@techfitness.com";
  NSString *cName = @"Stephen Kochan";
  NSString *cEmail = @"steve@kochan-wood.com";
  NSString *dName = @"Jamie Baker";
  NSString *dEmail = @"jbaker@kochan-wood.com";
  
  AddressCard *card1 = [[AddressCard alloc] init];
  AddressCard *card2 = [[AddressCard alloc] init];
  AddressCard *card3 = [[AddressCard alloc] init];
  AddressCard *card4 = [[AddressCard alloc] init];
  
  AddressBook *myBook = [AddressBook alloc];
  
  // first set up four address cards
  
  [card1 setName: aName andEmail: aEmail];
  [card2 setName: bName andEmail: bEmail];
  [card3 setName: cName andEmail: cEmail];
  [card4 setName: dName andEmail: dEmail];
  
  // now initialize the address book
  
  myBook = [myBook initWithName: @"Linda's Address Book"];
  
  printf ("Entries in address book after creation: %i\n",
              [myBook entries]);
              
  // Add some cards to the address book
  
  [myBook addCard: card1];
  [myBook addCard: card2];
  [myBook addCard: card3];
  [myBook addCard: card4];
  
  printf ("Entries in address book after adding cards: %i\n\n",
              [myBook entries]);
              
  // list all the entries in the book now
  
  [myBook list];
  
  [card1 release];
  [card2 release];
  [card3 release];
  [card4 release];
  [myBook release];
  [pool release];
  return 0;
}

didn't i declare dealloc in my interface file?
what is the syntax error before '{' token?

 

[Nutter]

You're only importing <Foundation/NSArray.h> in your header file. -(void)dealloc is declared <Foundation/NSObject.h>

I'd suggest that you change the import statement to the following:
#import <Foundation/Foundation.h>

This will include all the headers for the Foundation framework, including both NSObject.h and NSArray.h.

It isn't necessary to redeclare -(void)dealloc in your header file, as it's declared by the superclass, NSObject.

By the way, you can use -UTF8String instead of -cString.

 

[Krevnik]

Another game of spot the bug.

The bug is here, at the end of the list method:

-(void) list
{
  int     i, elements;
  AddressCard *theCard;
  
  printf ("\n======== Contents of: %s =========\n",
           [bookName cString]);
  elements = [book count];
  
  for ( i = 0; i < elements; ++i ) {
      theCard = [book objectAtIndex: i];
      printf ("%-20s %-32s\n", [[theCard name] cString],
                   [[theCard email] cString]);
  }
  
  printf("========================================\
          ============\n\n");
  
          
-(void) dealloc
{
  [bookName release];
  [book release];
  [super dealloc];
}

If you look closely, the list method isn't closed off. This leads to the series of compile errors you see. Fix that, and the dealloc undeclared error should go away too.

 

[jamesapp]

where should i close off list.
i tried at the end of

AddressCard *theCard;

got more error messages
i closed off list with '}', is that what you meant

 

[kainjow]

i closed off list with '}', is that what you meant

Yes, put the } right after your printf() function call and before the dealloc method.

 

[jamesapp]

tried to put '}' right after printf and before dealloc
got following error messages when i tried to compile

james-collinss-macbook-prorog15 jamescollins$ gcc -framework Foundation AddressBook.m prog15.11.m -o prog15.11
AddressBook.m: In function ‘-[AddressBook initWithName:]’:
AddressBook.m:8: warning: conflicting types for ‘-(id)initWithNameNSString *)name’
AddressBook.h:11: warning: previous declaration of ‘-(AddressBook *)initWithNameNSString *)name’
Undefined symbols:
".objc_class_name_AddressCard", referenced from:
literal-pointer@__OBJC@__cls_refs@AddressCard in ccBDrI05.o
ld: symbol(s) not found
collect2: ld returned 1 exit status

 

[iSee]

It actually compiled, so now you're on to other bugs!

Here's the one causing the first warning:

in the header, initWithName returns an AddressBook pointer, while in the .m file it returns an id:
Header:

-(AddressBook *) initWithName: (NSString *) name;

.m file:

-(id) initWithName: (NSString *) name

 

[kainjow]

Undefined symbols:
".objc_class_name_AddressCard", referenced from:
literal-pointer@__OBJC@__cls_refs@AddressCard in ccBDrI05.o
ld: symbol(s) not found
collect2: ld returned 1 exit status

Looks like you're not compiling AddressCard into your code. Try compiling like this:

gcc -framework Foundation [b]AddressCard.m[/b] AddressBook.m prog15.11.m -o prog15.11

 

[Eraserhead]

You also should put if blocks around the stuff you're releasing i.e.

if(bookName!=nil){
	[bookName release];
}
if(book!=nil){
	[book release];
}

 

[Krevnik]

You also should put if blocks around the stuff you're releasing i.e.

if(bookName!=nil){
    [bookName release];
}
if(book!=nil){
    [book release];
}

I have been curious, how needed is that? In my experience, calling release on a nil object is usually safe(ish).

 

[Cromulent]

I have been curious, how needed is that? In my experience, calling release on a nil object is usually safe(ish).

You said it yourself. Safe(ish) is not safe . Better be safe than sorry, I can imagine trying to debug a possible error relating from that to be rather stressful.

 

[Krevnik]

You said it yourself. Safe(ish) is not safe . Better be safe than sorry, I can imagine trying to debug a possible error relating from that to be rather stressful.

Well, the main reason I say safe-ish, is that I haven't seen a crash from calling release on a nil object... But yeah, defensive is usually better.

 

[iSee]

It *is* safe to send messages to nil (including release).
It will do nothing. The return value will be nil.

http://developer.apple.com/document....html#//apple_ref/doc/uid/TP30001163-CH11-SW7

 

[kainjow]

On the other hand if you're dealing with CoreFoundation types, you must check for NULL before releasing those when using CFRelease().

 

[GeeYouEye]

Nope, releasing nil in dealloc isn't just safe-ish, it's desired. Apple does it throughout Cocoa that way. There's a huge discussion of this very topic on Apple's Cocoa-dev mailing list. Go right ahead and get rid of those if's.

 

[Sbrocket]

[nil release]; is a perfectly fine message to send, so the if blocks are unnecessary.

See http://www.cocoabuilder.com/archive/message/cocoa/2008/4/18/204503 if you'd like to read up on the reasons and history for it, its a pretty good thread.

 

[Krevnik]

Nope, releasing nil in dealloc isn't just safe-ish, it's desired. Apple does it throughout Cocoa that way. There's a huge discussion of this very topic on Apple's Cocoa-dev mailing list. Go right ahead and get rid of those if's.

Awesome, now I know all those [var release] lines in my older code weren't the result of some delusion. I was being productively lazy.

 

[jamesapp]

compiled with AddressCard.m and program compiled
still confused about
warning: conflicting types for ‘-(id)initWithNameNSString *)name’
AddressBook.h:11: warning: previous declaration of ‘-(AddressBook *)initWithNameNSString *)name’

 

[kainjow]

Reread iSee's post. You need to keep the method declaration and implementation the same. They are different.

 

[jamesapp]

thanks