Why do I get a "parse error before '@' token" when I try to build this simple XCode project?

Complete newbie question. I'm learning Objective-C from Kochan's book. When I try to build the following very simple project, I keep getting a

parse error before '@' token

referring to the @property int numerator, denominator; statement in the Fraction.h file.

Here is the Fraction.h file:

#import <Foundation/Foundation.h>

@interface Fraction : NSObject
{
    int numerator;
    int denominator;
}

@property int numerator, denominator;

-(void) pr开发者_开发问答int;
-(void) setTo: (int) n over: (int) d;
-(double) convertToNum;

@end

Here is the Fraction.m file:

#import "Fraction.h"

@implementation Fraction

@synthesize numerator, denominator;

-(void) print
{
    NSLog(@"%i/%i", numerator, denominator);
}
-(void) setTo: (int) n over: (int) d
{
    numerator = n;
    denominator = d;
}
-(double) convertToNum
{
    if (denominator != 0)
        return (double) numerator/denominator;
    else
        return 1.0;
}

@end

Any help in understand why I am getting that parse error is much appreciated.

I found this on Objective-C 2.0 (but interestingly not in Kochan's book): "All Objective-C applications developed for Mac OS X that make use of the [above] improvements for Objective-C 2.0 are incompatible with all operating systems prior to 10.5 (Leopard)." So we've found the explanation. Thank you all.

Hello Scolfax welcome it seems your problem in @property int numerator, denominator; and NSLog(@"%i/%i", numerator, denominator);