NSOutlineView byItem reference

FROM : Gerald Hanks
DATE : Mon Apr 11 06:51:32 2005

I have a project in which I am using an NSOutlineView, some 
CharacterSet(s) (my own class) and some Character(s) (also my own 
class)

In my control object I have the delegate function:

- (void)outlineView:(NSOutlineView *)outlineView 
setObjectValue:(id)object forTableColumn:(NSTableColumn *)tableColumn 
byItem:(id)item {
   ...
   if([item isMemberOfClass:[CharacterSet class]]) {
       NSEnumerator * characterEnum;
       characterEnum = [[item characters] objectEnumerator];
       ...
   }
   ...
}

When I compile this code I get the following warnings:

Controller.m:343: warning: multiple declarations for method `characters'
/System/Library/Frameworks/AppKit.framework/Headers/NSEvent.h:141: 
warning: using `-(NSString *)characters'
CharacterSet.h:35: warning: also found `-(NSArray *)characters'
/System/Library/Frameworks/AppKit.framework/Headers/
NSTextStorageScripting.h:21: warning: also found `-(NSArray 
*)characters'
Controller.m:343: warning: `NSString' may not respond to 
`-objectEnumerator'

Everything runs the way it should since my CharacterSet class does in 
fact have a method 'characters' which returns the NSArray of 
characters, but I would like to know if there is a more appropriate way 
to do this so that I do not receive the compiler warnings.

As you can see I am fairly new to cocoa programming and would 
appreciate any and all suggestions.

--gerald