Simple Bool Function Malfunction

[Randeh]

Hey, I'm guessing my bool never returns true for some reason. There's no compiler error, it just continually prints back that the operator is invalid, even when the user enters a valid operater. I know I'm missing something glarlingly obvious in this section of my program, but I just can't spot it for the life of me:

#include <iostream>
#include <cstring>
using namespace std;

bool OpStatus(false);
char TestOp, UseOp;
int i;
void IsValidOp(char TestOp, int i);

void main()
     {	
     while (1) 
          {						                   
          cout << "Enter desired operation: ";
          cin >> TestOp;

          IsValidOp(OpStatus,i);
	if (OpStatus==false)
	{
                cout << "Invalid operator. Try again." << endl;
	continue;
	} else TestOp = UseOp;
          }
     }


void IsValidOp(char TestOp, int i)
	{
	char ValidOp[] = "+-*/cCxX";
	for (i=0; OpStatus=false, (i<strlen(ValidOp)); i++)
		{
		if (TestOp==ValidOp[i])
			OpStatus = true;
		}
	}

[sicarie]

Hey, I'm guessing my bool never returns true for some reason. There's no compiler error, it just continually prints back that the operator is invalid, even when the user enters a valid operater. I know I'm missing something glarlingly obvious in this section of my program, but I just can't spot it for the life of me:

#include <iostream>
#include <cstring>
using namespace std;

bool OpStatus(false);
char TestOp, UseOp;
int i;
void IsValidOp(char TestOp, int i);

void main()
     {	
     while (1) 
          {						                   
          cout << "Enter desired operation: ";
          cin >> TestOp;

          IsValidOp(OpStatus,i);
	if (OpStatus==false)
	{
                cout << "Invalid operator. Try again." << endl;
	continue;
	} else TestOp = UseOp;
          }
     }


void IsValidOp(char TestOp, int i)
	{
	char ValidOp[] = "+-*/cCxX";
	for (i=0; OpStatus=false, (i<strlen(ValidOp)); i++)
		{
		if (TestOp==ValidOp[i])
			OpStatus = true;
		}
	}

I think your problem might lie in the declaration:

bool OpStatus(false);

Try doing:

bool opStatus;

And then right before you use it, set it to whatever you want the initial value to be.

[sicarie]

And upon closer inspection:
[code]
for (i=0; OpStatus=false, (i<strlen(Valid Op)); i++)
[/quote]

You set OpStatus to false every time you go through the loop. Even if this is set to true, the next time to loop is done, it's set to false - wiping out true.

    OpStatus = false;
    for (i=0; (i<strlen(ValidOp)); i++) {

That will keep OpStatus from being reset every time.

[Randeh]

Changed the bool declaration to just bool OpStatus; and altered the function as follows:

 
void IsValidOp(char TestOp, int i)
     {
     char ValidOp[] = "+-*/cCxX";
     OpStatus = false;
     for (i=0; (i<strlen(ValidOp)); i++)
          {
          if (TestOp==ValidOp[i])
	OpStatus = true;
          }
       }

... and I'm still constantly getting a false returned! What I wouldn't give for an obvious solution once and a while.

[Ganon11]

You are going about this the wrong way. Instead of having a void function that changes a global boolean value, why not write a bool returning function? If you find the operator inside the ValidOp array, return true - if, after searching, you haven't found it, return false.

[Randeh]

Thanks, all makes much more sense than what I was trying!