Using protocols to avoid method signature mismatches on class methods

gistfile1.m

#import <Cocoa/Cocoa.h>

@protocol IdMethod
	+ (id) method;
@end

@interface IdClass : NSObject <IdMethod>
@end

@implementation IdClass
+ (id) method
{
	return @"hello!!";
}
@end



@protocol StructMethod
	+ (NSRect) method;
@end

@interface StructClass : NSObject <StructMethod>
@end

@implementation StructClass
+ (NSRect) method
{
	return CGRectMake(5,5,5,5);
}
@end

int main (int argc, char const *argv[])
{
	NSAutoreleasePool* pool = [[NSAutoreleasePool alloc] init];

	Class<IdMethod> a = [IdClass class];
	NSLog(@"%@", [a method]);

	Class<StructMethod> b = [StructClass class];
	NSLog(@"%@", NSStringFromRect([b method]));

	[pool drain];
	return 0;
}