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    <p>You can't. The template template parameter means that you take a template name <strong>without supplied template arguments</strong>.</p> <pre><code>Foo&lt; Param &gt; tt; </code></pre> <p>Here you can see that no values are supplied for <code>Param</code>. You'd take a template template parameter so that Foo itself could instantiate <code>Params</code> with any arguments it likes.</p> <p>Example:</p> <pre><code>template &lt; template &lt; int, int &gt; class X1&gt; struct Foo { X1&lt;1, 2&gt; member; X1&lt;42, 100&gt; foo(); }; template &lt;int N, int P&gt; struct A {}; template &lt;int X, int Y&gt; struct B {}; Foo&lt;A&gt; a_foo; //has a member of type A&lt;1, 2&gt;, foo returns A&lt;42, 100&gt; Foo&lt;B&gt; b_foo; //has a member of type B&lt;1, 2&gt;, foo returns B&lt;42, 100&gt; </code></pre> <hr> <p>But if you want your <code>Foo</code> to output those integers, it has to take real types, not templates. Secondly, the names of the template arguments (<code>X</code> and <code>Y</code>) are only meaningful where they are in scope. They are otherwise completely arbitrary identifiers. You can retrieve the values with simple metaprogramming:</p> <pre><code>#include &lt;cstdio&gt; template &lt;class T&gt; struct GetArguments; //partial specialization to retrieve the int parameters of a T&lt;int, int&gt; template &lt;template &lt;int, int&gt; class T, int A, int B&gt; struct GetArguments&lt;T&lt;A, B&gt; &gt; { enum {a = A, b = B}; }; //this specialization also illustrates another use of template template parameters: //it is used to pick out types that are templates with two int arguments template &lt;class X1&gt; struct Foo { int foo() { printf("ok%d %d\n", GetArguments&lt;X1&gt;::a, GetArguments&lt;X1&gt;::b); return 0; } }; template &lt; int X, int Y &gt; class Param { public: void print(); }; //this is to illustrate X and Y are not essential part of the Param template //in this method definition I have chosen to call them something else template &lt;int First, int Second&gt; void Param&lt;First, Second&gt;::print() { printf("Param&lt;%d, %d&gt;\n", First, Second); } int main() { Foo&lt; Param&lt;10, 20&gt; &gt; tt; tt.foo(); Param&lt;10, 20&gt; p; p.print(); return 0; } </code></pre>
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