Reassignment to a const variable that was declared in an if()

From: Oplec (anonymous_at_anonymous.cp)
Date: 10/31/03 

Date: Fri, 31 Oct 2003 10:22:42 GMT

Hi,

I thought that I understood how C++ allows for the declaration and
defining of variables within an if() statement and how the declared
variable can be used until the end of the major if() block.

        if (int a = /*...*/) {
                // ...
        }
        else if (a = /*variable a be assigned*/) {
                /* variable a can still be used here */
        }
        else {
                /* variable a can still be used here */
        }
        /* variable a can not be used here */

In the process of coding I used a const variable in the if statement and
then assigned to the const variable in the "else if" part, by mistake.
However, the GCC compiler that I am using compiled the code without any
warnings or errors returned. I read in TC++PL that a variable declared
const can only be initialized and never assigned. And that is why I have
written this post. Is GCC in error, or my understanding of standard C++?

        if (const int a = /*...*/) {
                // ...
        }
        else if (a = /*can a be assigned here???*/) {
                /* Can the variable be assigned to above and then used here with the
new value? */
        }

Thanks, oplec.

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