macOS What's wrong with this (rather simple) code?

[Doju]

I'm beginning programming in Obj-C, and the book I'm learning from seems to have some typos here and there and this example code the book gave fails to compile.

// First program example

int main (int argc, const char * argv[])
{
	NSAutoreleasePool * pool = [[NSAutoreleasePool alloc] init];
	
	int value1, value2, sum;
	
	value1 = 50;
	value2 = 25;
	sum = value1 + value2;
	
	NSLog (@”The sum of %i and %i is %i”, value1, value2, sum);
	
	[pool drain];
	return 0;
}

Why is that?

 

[lee1210]

What is the error? How did you compile? Is that your complete source, with any #includes?

-Lee

 

[Doju]

This is my error:

Build and Run in Xcode. Yes, that's the complete source.

 

[lee1210]

http://developer.apple.com/iphone/l...Foundation_Functions/Reference/reference.html

NSLog is not built-in/intrinsic. C and Objective-C don't have such a thing (there is a standard library). The link above tells you what framework NSLog is included with. You need to import the appropriate thing to use any function.

I'm not trying to be obtuse for fun, but it will rob you of a learning opportunity if I tell you exactly what to do.

-Lee

 

[kainjow]

Actually I think the problem is the quotes:

NSLog (@[COLOR="Red"][B]”[/B][/COLOR]The sum of %i and %i is %i[B][COLOR="Red"]”[/COLOR][/B], value1, value2, sum);

Those should be the normal " character.

 

[chown33]

... the book I'm learning from ...

Which book? Be specific.

 

[cromwell64]

You need to this import statement at the beginning of your code

#import <Foundation/Foundation.h>

in order for NSLog to be recognized.

if you have that, then the other problem looks like it is with the smart, or curly, quotes around the string...

”The sum of %i and %i is %i”

should be

"The sum of %i and %i is %i"

with straight double quote marks

 

[pilotError]

You have to be careful with cut/paste from PDF's. They seem to sneak those damn fancy quotes in when your not looking!

 

[Doju]

Oh, thanks guys. Fixing the quotes fixed the problem. Thanks. 😀

And the book is "Programming in Objective-C 2.0".