Question

I’m new to CPP, and I want to know how to run a function that isn’t in its scope. I’m used to doing such things in javascript, and I get an error CPP when I try to do that. What I mean is the below:

#include <iostream>

using namespace std;
int tic_h;
int tic_v;
void echo(string e_val){
   cout << e_val;
}
void c_mes(){
  echo("X|0|X\n");
  echo("-----\n");
  echo("X|0|X\n");
  echo("-----\n");
  echo("X|0|X\n");
  s_v();
}
void s_v(){
  echo("Please enter vertical coordinate: ");
  cin >> tic_v;
  if(tic_v<4&&tic_v>0){
    c_mes();
  }else{
    s_v();
  }
}
void s_h(){
  echo("Please enter horizontal coordinate: ");
  cin >> tic_h;
  if(tic_h<4&&tic_h>0){
    s_v();
  }else{
    s_h();
  }
}

int main(){
  s_h();
  return 0;
}

I get this error:

error: ‘sv’ was not declared in this scope on line 16

How can I make it work?

Answer 1

You should put a function prototype before using the function, for the compiler to know what it is going to be.

Put

void s_v(); // prototype your functions, this is usually done in include files

Right after the #include line.