Question about parameter variables

[brh11]

Hello Everyone,

For the past few years I've been learning c++ but only these few months to really get into it. I've been thinking about this non stop and wondering if someone could answer this question.

I understand the usage of this but I am curious to know how this is done.Below in the code on line 19.The parameters are set for a string which then is used to output on the line below that.What I am wondering is why are the parameters needed and you are not able to just use the string name,Even though mystring is not using the x variable.

Thank you!

#include <iostream>

using namespace std;

string mystring = "The number you are looking for does not exists";
int main()
{
  try{
    int momsAge =67;
    int sonsAge = 99;


  if(sonsAge>momsAge){

    throw mystring ;

  }

  }catch(string x ){

  cout<<   mystring << endl;
  }





}

[poteto]

The parameters are not needed. You can use (...), all exceptions will output the same. If mystring was inside try's scope, you would need to use x.

[MiiNiPaa]

In this case parameters are not needed. However it is not a good style even here: you should receive reference to exception, not the copy.

As poteto said, if your code would be something like:

#include <iostream>
#include <string> //Do not use std::string without this header
using namespace std;

int main()
{
  try{
    string mystring = "The number you are looking for does not exists";
    int momsAge =67;
    int sonsAge = 99;
    if(sonsAge>momsAge)
      throw mystring ;
  } catch(string& x ){
    cout<<   mystring << endl;
  }
}

It would not work, and you will have to use parameter x.