Welcome to OStack Knowledge Sharing Community for programmer and developer-Open, Learning and Share
Welcome To Ask or Share your Answers For Others

Categories

0 votes
262 views
in Technique[技术] by (71.8m points)

ios - arrow operator in objective-c

I have a question, here's the code:

@interface MyFoo : NSObject {
    NSString *nameStr;
}
@end
@implementation MyFoo
- (id)init {
    self = [super init];
    if (self) {
        self->nameStr = [@"some value of the string that is set right into the private ivar" copy];
    }
    return self;
}
@end

The question is: ignoring all the C++ rules, ignoring memory dump vulnerability, why exactly I shouldn't use such arrow operator syntax? Is there somewhere in Apple documentation a rule which says that it's incorrect because in future class may be represented differently than a pointer to a struct in runtime etc. ?

Thanks in advance!

See Question&Answers more detail:os

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome To Ask or Share your Answers For Others

1 Answer

0 votes
by (71.8m points)

The use of self->someIvar is identical to someIvar. It's not wrong but it's not needed either.

The only time I use the arrow notation is in an implementation of copyWithZone: so I can copy each of the ivars that don't have properties.

SomeClass *someCopy = ...
someCopy->ivar1 = ivar1; // = self->ivar1
someCopy->ivar2 = ivar2; // = self->ivar2

Where are you seeing anything that says you shouldn't use such arrow operator syntax?


与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome to OStack Knowledge Sharing Community for programmer and developer-Open, Learning and Share
Click Here to Ask a Question

...