带模板和枚举的条件运算符使用不正确？

Question

我想尝试从每个值返回一个值，但由于错误使用条件运算符而导致错误。

#include<iostream>
using namespace std;

enum class Fruit { apple, orange, pear };

enum class Color { red, green, orange };

// no problem till here but conditional operators are causing problems,i am 
// getting so many errors.does anyone knows the right way of writing them here?
template <typename T> struct Traits;

template <> 

struct Traits<Fruit>
{
static string name(int index)
{
int var=(index<=2?(index!=0?(index==1? return "orange": return "pear"):return "apple"): return "unknown"); 

}     
};
template <> 

struct Traits<Color>
{
static string name(int index)
{
int var=(index<=2?(index!=0?(index==1? return "green": return "orange"): 

return "red"): return "unknown");  //something wrong with the use of the operators       
} 
};

驱动程序代码

int main()
{
 int t = 0; std::cin >> t;

for (int i=0; i!=t; ++i) {
    int index1; std::cin >> index1;
    int index2; std::cin >> index2;
    cout << Traits<Color>::name(index1) << " ";
    cout << Traits<Fruit>::name(index2) << "\n";
}
}

如何正确使用它们