How get name macros from value?

Question

I write #define macros

I want to have a function or a macro that prints its name when I give it a value

for example :

`

#define ten 10

 string printName(int value);
int main()
{
    cout<<printName(10);
}

`

output : ten

A solution or code sample

What name? Do you mean print the number using words? Well, what have you tried so far? This is not code-writing service. — Quimby, Nov 01 '22 at 06:17
Okay, and what did you try so far? What problems are you having with your solution? — Quimby, Nov 01 '22 at 06:22
The general rule for C++ is NOT to use since macros are not typesafe (unless you have to). In this case `static constexpr int ten{10};'` would be a better approach to define a constant. Side note, stop using [`using namespace std;`](https://stackoverflow.com/questions/1452721/why-is-using-namespace-std-considered-bad-practice) — Pepijn Kramer, Nov 01 '22 at 06:35

score 1 · Answer 1 · answered Nov 01 '22 at 06:25

The pre processor doesn't allow what you are trying to do

Also consider:

#define ten 10
#define xxx 10

string printName(int value);
int main()
{
    cout<<printName(10);
}

What would you expect it to output ? Just because it makes sense to you doesn't mean it makes sense to the compiler / cpp.

score 0 · Accepted Answer · answered Nov 01 '22 at 06:44

Use of macros should be avoided wherever possible.

Instead you could use a std::map<int, std::string> for your purpose:

int main()
{
    const std::map<int, std::string> printName{{10, "ten"}, {11, "eleven"}};//add more if you want 
    
    std::cout << printName.at(10) << std::endl;  //prints ten
}

How get name macros from value?

2 Answers2