Re: extern variables

From:

James Kanze <james.kanze@gmail.com>

Newsgroups:

comp.lang.c++

Date:

Sun, 3 May 2009 02:09:49 -0700 (PDT)

Message-ID:

<96310d47-75e9-4e57-9707-09e8c74a1486@h23g2000vbc.googlegroups.com>

On May 2, 3:23 am, Andrey Tarasevich <andreytarasev...@hotmail.com>
wrote:

Comp1...@yahoo.co.uk wrote:

For example, I ran the following program:

// Code below in a source file
#include "SomeHeader.h"
#include <iostream>

int main ()
{
int j = doropi;
std::cout << j;
}

//Code in SomeHeader.h
const int doropi = 9;

The result of the program was that 9 was output. However,
what I expected was a compile error based on the rule (or
what I thought was the rule) that const definitions have
file scope

There's never been such a rule. The scope of an identifier
depends on the point and the manner of its declaration. It is
not tied in any way to the declaration's being a "const
definition" or not.

The scope, no. But the default linkage, and whether a
declaration is a definition or not, does depend on whether the
object is const.

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James Kanze (GABI Software) email:james.kanze@gmail.com
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