converting a variable name to a string in C++

Question

I\'d like to output some data to a file. For example assume I have two vectors of doubles:

vector data1(10);
vector data2(10); 
         


        

Answer 1

I had the same problem. After a little bit of experimentation I created following macros that convert names of variables, fields, functions, methods and types to strings.

#define MACRO_VARIABLE_TO_STRING(Variable) (void(Variable),#Variable)

#define MACRO_FUNCTION_TO_STRING(Function) (void(&Function),#Function)

#define MACRO_METHOD_TO_STRING(ClassName,Method) (void(&ClassName::Method),#Method)

#define MACRO_TYPE_TO_STRING(Type) (void(sizeof(Type)),#Type)

The code uses comma operator and void conversion to force compiler to check if variable, function, etc. really exists. The nice thing is that it works well with uninitialized variables too. I tested it on both VC and GCC with all pedantic options I found out without any warning messages.

int GetAndPrintValue(const char* VariableName)
{
   std::cout << VariableName << std::endl;
   return 10;
}

int Variable=GetAndPrintValue(MACRO_VARIABLE_TO_STRING(Variable));

I use such code when I write parsers that reads data from input stream and if parsed variable is out of bounds it throws an exception with name of variable that failed my validity checks.