https://stackoverflow.com/questions/45790194/c-utility-to-convert-long-switch-statement-into-the-concise-function-call-whic

cleanSwitch.cpp

#include <string>
#include <iostream>

#define SWITCH(CASE, VALUE) case CASE : return VALUE; 

#define LIST_OF_VARIABLES \
    SWITCH(2 , "two") \
    SWITCH(5 , "five") \
    SWITCH(7 , "seven")

template<class RetValue>
RetValue switchReturn(const int key){
    // makes the actual switch case
    switch(key) {
      LIST_OF_VARIABLES 
      default: throw "fail";
    }
    #undef SWITCH
}

template<class RetValue>
void match(const int key,RetValue &val) {
    val = switchReturn<RetValue>(key);
}    

int main(){

    int num = 5;
    std::string str;

    match(num,str);
    std::cout << str;

    //here str == "five"
}