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copied!<p>I think you could write a small <code>myint</code> class which makes sure that the <code>int</code> you pass is always greater than <code>1</code>:</p> <pre><code>struct myint { int data; myint(int i) : data(i) { assert(data > 1); } }; </code></pre> <p>Now use it in your class:</p> <pre><code>class B : public A{ public: B(myint dim) //this can still take int, due to implicit conversion! : A(dim.data) { } } </code></pre> <p>Note that you can still construct <code>B</code> passing <code>int</code>, as it will implicitly convert into <code>myint</code> and while the conversion takes place (implicitly), it will test the <em>assert</em>, and if that succeeds, only then you would be able to pass <code>dim.data</code> to the base class <code>A</code>. If the <em>assert</em> fails, your program will abort before entering into the base class constructor (without initializing anything in derived class also).</p> <hr> <p>You could even generalize it as:</p> <pre><code>//Summary : gint<N> makes sure that data > N template<int N> struct gint //call it greater int { int data; gint(int i) : data(i) { assert(data > N); } //Use N here! }; </code></pre> <p>Now use it in your class:</p> <pre><code>class B : public A{ public: B(gint<1> dim) //the template argument 1 makes sure that dim.data > 1 : A(dim.data) { } } </code></pre> <p>If you need another class, for example:</p> <pre><code>class Xyz : public A{ public: B(gint<10> dim) //gint<10> makes sure that dim.data > 10 : A(dim.data) { } } </code></pre> <p>Cool, isn't?</p>

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