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Re: References to classess
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Re: References to classess


  • Subject: Re: References to classess
  • From: Andy Lee <email@hidden>
  • Date: Thu, 25 Apr 2002 16:13:09 -0400

At 2:29 PM -0500 4/25/02, Al Kirkus wrote:
I have a class structure in which one class uses another but the other uses the first. I can get it to compile by using the @class directive instead of including the one of the header files

Are you using #include or #import? You should use #import.

but I receive warnings like:

Record.m:27: warning: `Column' does not respond to `retain'

The Column class is the one I used @class on.

All the @class does is tell the compiler there exists a Column class. You can use this to help compile a .h file that has Column instance variables, if you don't want to (or can't) import the Column.h header.

To compile the .m file without warnings (as you should), you need to import Column.h so the compiler knows what messages Column responds to.

You can use

@class Column;

in your OtherClass.h file, and

#import "Column.h"

in your OtherClass.m file so the compiler will see what methods Column responds to.

--Andy
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References: 
 >References to classess (From: "Al Kirkus" <email@hidden>)

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