gistfile1.m

// Get property by name: "performSelector:"

- (void)encodeWithCoder:(NSCoder *)encoder {
	for(int i=0; i<kFieldCount; i++) {
		NSString *fieldName = [[NSString alloc]initWithFormat:@"field%d", i+1];
		//NSString *field = [self performSelector:sel_getUid([fieldName UTF8String])];
		NSString *field = [self valueForKey:fieldName];
		[encoder encodeObject:field forKey:fieldName];
		[fieldName release];
	}
	
//	[encoder encodeObject:field1 forKey:kField1Key];
//	[encoder encodeObject:field2 forKey:kField2Key];
//	[encoder encodeObject:field3 forKey:kField3Key];
//	[encoder encodeObject:field4 forKey:kField4Key];
}

gistfile2.m

// Set property by name: "setValue:forKey:"

- (id)initWithCoder:(NSCoder *)decoder {
	if (self = [super init]) {
		for(int i=0; i<kFieldCount; i++) {
			NSString *fieldName = [[NSString alloc]initWithFormat:@"field%d", i+1];
			NSString *field = [decoder decodeObjectForKey:fieldName];
			[self setValue:field forKey:fieldName];
			[fieldName release];
		}
		
//		field1 = [decoder decodeObjectForKey:kField1Key];
//		field2 = [decoder decodeObjectForKey:kField2Key];
//		field3 = [decoder decodeObjectForKey:kField3Key];
//		field4 = [decoder decodeObjectForKey:kField4Key];
	}
	return self;
}