Question

I have a C++ class in my Objective C ARC project. The class is derived from a pure C++ class and adds a platform specific implementation for my iOS project. I want to call Objective C functions and frameworks there.

I implemented the platform specific parts using C++11 lambda functions. Can I do it that way? Any hidden pitfalls (especially because my iOS project uses ARC)?

bool MyDerivedCPPClass::getValue(const std::string& stdKey, std::string& stdValue) const
{
    NSString *key = [NSString stringWithUTF8String:stdKey.c_str()];

    // Do ObjC stuff

    if(value)
    {
        stdValue = std::string([value cStringUsingEncoding:NSUTF8StringEncoding]);
        return YES;
    }
    else
    {
        return NO;
    }
}

Answer 1

It looks fine (generally Objective-C does not interfere with C++), aside from:

• Why are you defining a lambda just to call it immediately?
• C++ bool should be true/false, not YES/NO
• Make sure the thread that this runs on has an autorelease pool