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    <p>Without seeing the definition of <code>MyClass</code> the problem is not quite clear. I believe anyway that you want to get <code>MyClass::_myVar</code> initialized without code to iteratively fill it with the <code>MyClass::metaFunction()</code> values.</p> <p>You code suggests that <code>MyClass::_myVar</code> is a static class member. In that case your initialization of the member is perfectly good C++11 as it stands. The following program illustrates (GCC 4.6.3):</p> <pre><code>#include &lt;iostream&gt; /* MyClass Version 1 */ template&lt;unsigned int DIM&gt; struct MyClass { static constexpr unsigned int metaFunction( const unsigned int k, const unsigned int n, const unsigned int dim); static const unsigned int _myVar[2][3]; }; template&lt;unsigned int DIM&gt; inline constexpr unsigned int MyClass&lt;DIM&gt;::metaFunction( const unsigned int k, const unsigned int n, const unsigned int dim) { return (((n &lt; dim) &amp;&amp; (k &lt; n)) ? (1&lt;&lt;(n-k)) : (0)); } template&lt;unsigned int DIM&gt; const unsigned int MyClass&lt;DIM&gt;::_myVar[2][3] = { { metaFunction(0, 0, DIM), metaFunction(0, 1, DIM), metaFunction(0, 2, DIM) }, { metaFunction(1, 0, DIM), metaFunction(1, 1, DIM), metaFunction(1, 2, DIM) } }; template&lt;unsigned int DIM&gt; inline constexpr unsigned int MyClass&lt;DIM&gt;::metaFunction( const unsigned int k, const unsigned int n, const unsigned int dim) { return (((n &lt; dim) &amp;&amp; (k &lt; n)) ? (1&lt;&lt;(n-k)) : (0)); } using namespace std; int main(void) { MyClass&lt;3&gt; mine; for (int i = 0; i &lt; 2; ++i) { for (int j = 0; j &lt; 3; ++j) { cout &lt;&lt; mine._myVar[i][j] &lt;&lt; endl; } } return 0; } </code></pre> <p>This inclines me to think that <code>MyClass::_myVar</code> is <em>not</em> a static member - although why this array of integer constants would not be static I am not sure. If that is the case, then you can initialize the member in the default constructor using the <a href="http://en.wikipedia.org/wiki/C%2B%2B11#Uniform_initialization" rel="nofollow">uniform initialization provision of C++11</a>:</p> <pre><code>/* MyClass Version 2 */ template&lt;unsigned int DIM&gt; struct MyClass { MyClass() : _myVar{ { MyClass::metaFunction(0, 0, DIM), MyClass::metaFunction(0, 1, DIM), MyClass::metaFunction(0, 2, DIM) }, { MyClass::metaFunction(1, 0, DIM), MyClass::metaFunction(1, 1, DIM), MyClass::metaFunction(1, 2, DIM) } }{} static constexpr unsigned int metaFunction( const unsigned int k, const unsigned int n, const unsigned int dim); const unsigned int _myVar[2][3]; }; </code></pre> <p>In neither case is the <code>constexpr</code> attribute of <code>metaFunction</code> actually necessary for compilation. And if <code>constexpr</code> is removed then <code>/* MyClass Version 1*/</code> is also good for C++03.</p>
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