How do you use a string or char to identify a variable by name in C++?

Question

What I mean is, how do I use a char, which I can iterate, to identify a variable? So if:

int cheese = 1337;
string identifier = "cheese";

How do I use this string "identifier" to identify the variable cheese and return its value?

C++ ulike Java does not have reflection so a program once is fully compiled, linked and loaded, it loses all reference to symbol names. The only thing is had is addresses. — doron, Dec 11 '16 at 20:51
Also https://stackoverflow.com/questions/2911442/access-variable-value-using-string-representing-variables-name-in-c — Baum mit Augen, Dec 11 '16 at 20:54

score 7 · Accepted Answer · answered Dec 11 '16 at 20:44

7

You don't.

Instead, you lay out your data differently, perhaps using a key-value store?

std::map<std::string, int> myData;
myData["cheese"] = 1337;

// ...

const std::string identifier = "cheese";
std::cout << myData[identifier] << '\n';   // 1337

answered Dec 11 '16 at 20:44

Lightness Races in Orbit

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I see. Hmm. I there any way to do it in Java? Apart from using the hashmaps, or other dictionary storage? – Jack Raiden Dec 11 '16 at 20:57
@JackRaiden: in... Java??? – Lightness Races in Orbit Dec 12 '16 at 11:03

score 1 · Answer 2 · answered Dec 11 '16 at 20:51

Looks like you are looking for map

#include <iostream>
#include <map>

using namespace std;

int main()
{
    map<string, int> vars;
    vars.insert(make_pair("cheese", 1337));
    vars.insert(make_pair("geese", 1338));
    if (vars.find("cheese") != vars.end())
        cout << vars.at("cheese");
    return 0;
}

How do you use a string or char to identify a variable by name in C++?

2 Answers2