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I want to convert an objective c code to objective cpp and use it in my application. Given the following code:

        CFTypeRef dynamicValue = (__bridge CFTypeRef)([[NSBundle bundleWithPath:aStr] objectForInfoDictionaryKey: @"CFPlugInDynamicRegistration"]);
        BOOL removeFlag = NO;
        if(dynamicValue == nil)
            removeFlag = NO;
        else if( CFGetTypeID(dynamicValue) == CFBooleanGetTypeID()  )
            removeFlag = CFBooleanGetValue(dynamicValue);
        else if( CFGetTypeID(dynamicValue) == CFStringGetTypeID()  )
            removeFlag = ( [[(__bridge NSString*)dynamicValue lowercaseString] isEqualToString:@"yes"] ? YES:NO);
        if( removeFlag )
            [unloadedArray addObject:aStr];
            [sortedArray removeObjectAtIndex:hoge];
I get an error when changing the file name from file.m to file.mm and  building: "no matching function for call to 'CFBooleanGetValue'"
I tried to #include <CoreFoundation/CFNumber.h> but I get the same error (I guess it's an ifdef issue).
Do you know any way I can cast without the missing function? Should I try to use the same function anyway?
                That is not what I experienced. I put OP's code into a main.mm file. After adding the static cast for the CFBooleanGetValue argument, the code compiled and linked without problems. No manual linking necessary.
– Martin R
                Aug 24, 2017 at 21:15
                @MartinR, Ah, right! I think all apps got linked implicit  with CoreFoundation anyway. And Foundation.h already includes CoreFoundation.h.
– Cy-4AH
                Aug 25, 2017 at 10:01
 NSString *aStr = @"";
    CFTypeRef dynamicValue = (__bridge CFTypeRef)([[NSBundle bundleWithPath:aStr] objectForInfoDictionaryKey: @"CFPlugInDynamicRegistration"]);
    BOOL removeFlag = NO;
    if(dynamicValue == nil)
        removeFlag = NO;
    else if( CFGetTypeID(dynamicValue) == CFNumberGetTypeID()  )
        removeFlag = [(__bridge NSNumber *)dynamicValue boolValue];
    else if( CFGetTypeID(dynamicValue) == CFStringGetTypeID()  )
        removeFlag = ( [[(__bridge NSString*)dynamicValue lowercaseString] isEqualToString:@"yes"] ? YES:NO);
    if( removeFlag )
        [unloadedArray addObject:aStr];
        [sortedArray removeObjectAtIndex:hoge];
                What about CFGetTypeID(dynamicValue) == CFBooleanGetTypeID(), your example handles only CFNumberGetTypeID and CFStringGetTypeID, while my problem occurs when it's CFBooleanGetTypeID
– benams
                Aug 23, 2017 at 8:51
In C++ a conversion from a void *  (here: CFTypeRef) to a 
pointer of a different type (here: CFBooleanRef aka __CFBoolean *) requires an explicit
cast. So this would solve the issue:
removeFlag = CFBooleanGetValue(static_cast<CFBooleanRef>(dynamicValue));
But actually I would forget about the CF types and bridging, and change the code to
id dynamicValue = [[NSBundle bundleWithPath:@"path"] objectForInfoDictionaryKey: @"CFPlugInDynamicRegistration"];
BOOL removeFlag = NO;
if ([dynamicValue isKindOfClass:[NSNumber class]]) {
    removeFlag = ((NSNumber *)dynamicValue).boolValue;
} else if ([dynamicValue isKindOfClass:[NSString class]]) {
    removeFlag = [((NSString *)dynamicValue).lowercaseString isEqualToString:@"yes"];
This compiles in Objective-C and Objective-C++. 
                Your first example won't compile in objective c++, because of the CFBooleanGetValue - that's the root of my problem... About the second one - is it safe to assume that the king is either NSNumber  or NSString ? it means that Boolean is kind of NSNumber?
– benams
                Aug 23, 2017 at 8:50
                @benams: Actually I tried my first example in an .mm file and it compiled without problems. – If the value is something else then none of the if-blocks will be executed, and the boolean variable remains NO. That is the same behaviour as in your code.
– Martin R
                Aug 23, 2017 at 8:52
        
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