Question

while working in try-catch in came across this error. But I cant trace out the reason for this error though I surfed the net and SO.

My code is…

int main()
{
Queue q;
int choice,data;

 while(1)
 {
  choice  = getUserOption();
  switch(choice)
  {
   case 1:
     cout<<"\nEnter an element:";
     cin>>data;
     q.enqueue(data);
     break;
   case 2:
     int element;
     element = q.dequeue();
     cout<<"Element Dequeued:\n"<<element;
     break;
   case 3:
     q.view();
     break;
   case 4:
     exit(EXIT_SUCCESS);
  }
  catch(UnderFlowException e)
  {
   cout<<e.display();
  }
  catch(OverFlowException e)
  {
   cout<<e.display();
  }

 }// end of while(1)

       return 0;
}

For me everything in the above code seems to be correct. But g++ complier is throwing…

muthu@muthu-G31M-ES2L:~/LangFiles/cppfiles/2ndYearLabException$ g++ ExceptionHandlingEdited.cpp
ExceptionHandlingEdited.cpp: In member function ‘void Queue::enqueue(int)’:
ExceptionHandlingEdited.cpp:89:97: warning: deprecated conversion from string constant to ‘char*’
ExceptionHandlingEdited.cpp: In member function ‘int Queue::dequeue()’:
ExceptionHandlingEdited.cpp:113:95: warning: deprecated conversion from string constant to ‘char*’
ExceptionHandlingEdited.cpp: In member function ‘void Queue::view()’:
ExceptionHandlingEdited.cpp:140:66: warning: deprecated conversion from string constant to ‘char*’
ExceptionHandlingEdited.cpp: In function ‘int main()’:
ExceptionHandlingEdited.cpp:185:3: error: expected primary-expression before ‘catch’
ExceptionHandlingEdited.cpp:185:3: error: expected ‘;’ before ‘catch’
ExceptionHandlingEdited.cpp:189:3: error: expected primary-expression before ‘catch’
ExceptionHandlingEdited.cpp:189:3: error: expected ‘;’ before ‘catch’

Answer 1

You can’t have a catch without a try. Put the line:

try {

before your while statement.

If you want to get rid of the warnings about the string constants, you’ll probably have to change the types to const char * or explicitly cast/copy them. Or you can use the -Wno-write-strings option to gcc.