nested functions are disabled, use -fnested-functions to re-enable-Objective C

I am getting errors when porting this map into Objective C.

typedef map<uint32_t,string>EventMapType;
EventMapType cEventMap;

error: nested functions are disabled, use -fnested-functions to re-enable error: expected '=', ',', ';', 'asm' or 'attribute' befor开发者_开发问答e '<' token

error: cannot find protocol declaration for 'uint32_t'

error: cannot find protocol declaration for 'string'

error: expected ';' before 'cEventMap'

compile the source as objective-c++ (use mm extension)