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POnamespace and private static class members
 

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    <p>Why does this work:</p> <pre><code>#include "iostream" class Something { private: static int s_nIDGenerator; int m_nID; friend int main(); public: Something() { m_nID = s_nIDGenerator++; } int GetID() const { return m_nID; } }; int Something::s_nIDGenerator; int main() { Something::s_nIDGenerator = 1; Something cFirst; Something cSecond; Something cThird; using namespace std; cout &lt;&lt; cFirst.GetID() &lt;&lt; endl; cout &lt;&lt; cSecond.GetID() &lt;&lt; endl; cout &lt;&lt; cThird.GetID() &lt;&lt; endl; return 0; } </code></pre> <p>it prints:</p> <pre><code>1 2 3 </code></pre> <p>And this fail:</p> <pre><code>#include "iostream" namespace test { class Something { private: static int s_nIDGenerator; int m_nID; friend int main(); public: Something() { m_nID = s_nIDGenerator++; } int GetID() const { return m_nID; } }; }; int test::Something::s_nIDGenerator; int main() { using namespace test; Something::s_nIDGenerator = 1; // or test::Something::s_nIDGenerator = 1; same effect if not using using. Something cFirst; Something cSecond; Something cThird; using namespace std; cout &lt;&lt; cFirst.GetID() &lt;&lt; endl; cout &lt;&lt; cSecond.GetID() &lt;&lt; endl; cout &lt;&lt; cThird.GetID() &lt;&lt; endl; return 0; } </code></pre> <p>With the compiler error message of:</p> <pre><code>**** Internal Builder is used for build **** g++ -O0 -g3 -Wall -c -fmessage-length=0 -o src\tuttest1.o ..\src\tuttest1.cpp ..\src\tuttest1.cpp: In function 'int main()': ..\src\tuttest1.cpp:23:5: error: 'int test::Something::s_nIDGenerator' is private ..\src\tuttest1.cpp:27:13: error: within this context Build error occurred, build is stopped Time consumed: 161 ms. </code></pre> <p>How do I get the 2nd example to work using the namespace test?</p> <p>How/Why is the namespace declaration around the object preventing the static member form being accessible?</p> <hr> <p>Per my comment to @zmo, here is what I got to work based on his clue:</p> <p>(comment doesn't have the space or formatting for this, and I had to edit because I couldn't set this an answer.... (what ever it takes.)</p> <pre><code>#include "iostream" namespace test { class Something { private: static int s_nIDGenerator; int m_nID; friend void load(int); public: Something() { m_nID = s_nIDGenerator++; } int GetID() const { return m_nID; } }; int Something::s_nIDGenerator; void load (int value) { Something::s_nIDGenerator = value; } }; int main() { using namespace test; load (1); Something cFirst; Something cSecond; Something cThird; using namespace std; cout &lt;&lt; cFirst.GetID() &lt;&lt; endl; cout &lt;&lt; cSecond.GetID() &lt;&lt; endl; cout &lt;&lt; cThird.GetID() &lt;&lt; endl; return 0; } </code></pre> <p>I am still a little loose as to the "what's up with static members being <strong><em>in a class and a namespace</em></strong> not working?" What's up with this? Why didn't <code>test::Something::s_nIDGenerator</code> work? (still a part of my original question.) So, we are half-answered, so far.</p> <p>I want to know <strong><em>why</em></strong> this didn't work so I don't walk into this rake again.</p>
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