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iOS Object-Oriented Objective-C Diving Deeper - Classes, Properties and Methods Custom Classes Continued

Ryan Jin
Ryan Jin
15,337 Points
Posted by Ryan Jin
Ryan Jin
15,337 Points

How can if operation work with nonboolean

In this video, there is this piece of code.

-(id)init {
    self = [super init];

    NSLog(@"%@\n", self);

    if (self) {
        self.itemsOrdered = [[NSMutableArray alloc]init];
    }

    return self;
}

I am wondering how can if statement be used to compare a self. Is it checking to see if self is nill or not, or is self a boolean type. I have printed it to the console, and it is not a boolean.

1 Answer

jcorum
jcorum
71,816 Points

It's shorthand for a boolean: self != nil.

Here's a great article on the subject: https://www.mikeash.com/pyblog/the-how-and-why-of-cocoa-initializers.html