RE: [LUG] A programming problem

[James Ogden <zemned@xxxxxxxxxx>]

On Thu, 2003-05-08 at 08:41, Darke, Clive wrote:
> The problem here is scoping I think.  While it is perfectly legal to declare
> a new variable after executable code in C++ (unlike C earlier than C99) that
> is not the problem, it is the initialization.  In case 0, c is initialized;
> in case 1 it is not.  The key is that a case statement does not generate a
> block of scope automatically, you have to explicitly define one.  I think
> you probably meant:
> 
> 	case 0 :
> 	{
> 	   int * c = new int;
> 	   // .... etc
> 	   break;        // can be inside or outside this block
> 	}
> 	case 1 :
> 	{
> 	   int * d = new int;
> 	   break;
> 	}
> 
> ... and this is not because you are new to C++, I showed this to a couple of
> other wrinkly coders and they didn't see it either!
> 
> Clive
> (wrinkly coder)




Oops I placed the {} on my example code for compilation as a matter of habit.
I think my subconscious got this one before my conscious mind had a chance to react.
I went back to the code I wrote to test the problem this morning and found that I had
indeed placed the {} around the statement.  I must have been so eager to get back
with the GCC problem as to completely ignore the real issue.  On my compiler, 
the following code works if you do g++ <filename> but not gcc <filename>.

int main() {
   int * a = new int;
   int b;
   switch (b) {
   case 0 :
     {
        int * c = new int;
       //       int * c;               
       //       c = new int;         
     }
         break;
      case 1 :
	{	
         int * d = new int;
         break;
	}		
   }
   return 0;
}




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