Passing an array of variables by reference

[manojg]

Hi,

I define an integer variable and pass it by reference to a function.

int func(int &x)
{
// do something
}

int x;
func(x);

However, I have not only one variable but an array of variables with its predefined name. How do I pass to the function by using loop? Example:

int x, y, z;
func(x);
func(y);
func(z);

How can I do this by using loop? Any suggestion?
Thanks.

[cire]

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// http://ideone.com/KX3ciT #include <iostream> void double_it(int& val) { val *= 2; } void print_it(int val) { std::cout << val << '\n'; } int main() { int values[10] = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 }; for (auto value : values) print_it(value); std::cout << '\n'; for (auto& value : values) double_it(value); for (auto value : values) print_it(value); std::cout << '\n'; }

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[manojg]

Thanks for quick reply. I understood this. But my question was something different. Rather than puting value in the array values[], I want to put variable names. I am having problem because variable names are pre-defined. I want to doe something like this:

int values[] = {x, y, z};

where x,y and z are just variable name.

Let look it another way. I have a lots of variables already defined such are

int a, b, c, d, ........., x, y, z;

Now, I want to pass these variables by reference, like this:

int func(int &x)
{
return x++;
}

cout << func(x) << endl;

For few variable, I can call this function for each variable separately, but if there are a lots then I want to use loop. How can I use loop?

[LB]

Why do you have a lot of variables that you need to loop through? That's a sign of poor design.

If you have to, you can use a variadic template function, but I recommend rethinking your design first.

[manojg]

Actually, I am using external library which requires to pass variable by reference and there are many variables that need to pass.

[LB]

Unless you go into more details, the current answer to your question is "no".

[dhayden]

int *vars[3] {&x, &y, &z};
for (int i=0; i<3; ++i) {
   func(vars[i]);
}

[manojg]

dhayden, thanks it works.