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    <p>Macros are expanded before any code is compiled, so unfortunately they don't have any concept of types.</p> <p>Depending on your needs, you might be able to use a traits class instead though. It's theoretically a bit more efficient and portable than RTTI and typeid, but it only works for types you've explicitly told it about. For example:</p> <pre><code>template &lt;typename T&gt; struct Traits { static const char * TYPE_NAME; }; // Generic definition as a fall-back: template &lt;typename T&gt; const char * Traits&lt;T&gt;::TYPE_NAME = "unknown"; // Explicit definitions template &lt; &gt; const char * Traits&lt; int &gt;::TYPE_NAME = "int"; template &lt; &gt; const char * Traits&lt; float &gt;::TYPE_NAME = "float"; template &lt; &gt; const char * Traits&lt; ExampleClass &gt;::TYPE_NAME = "ExampleClass"; </code></pre> <p>The explicit definitions are a bit cumbersome, so you could create a macro to make them more readable:</p> <pre><code>#define DECLARE_TYPE_TRAIT(name) template &lt; &gt; const char * Traits&lt;name&gt;::TYPE_NAME = #name; DECLARE_TYPE_TRAITS(int) DECLARE_TYPE_TRAITS(float) DECLARE_TYPE_TRAITS(ExampleClass) </code></pre> <p>Using the traits class in your code is really easy. You just instantiate the traits template on whatever type you want to look up, and access the TYPE_NAME member:</p> <pre><code>int foo; ExampleClass blah; cout &lt;&lt; Traits&lt;decltype(foo)&gt;::TYPE_NAME &lt;&lt; endl; cout &lt;&lt; Traits&lt;decltype(blah)&gt;::TYPE_NAME &lt;&lt; endl; </code></pre>
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    1. POIs there any way to convert decltype to string in a macro?
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    1. USPeter Bloomfield
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    1. COThanks - the solution I went for was actually just using the typename as an argument to the macro - it's effectively the same as this although more specified to my particular case.
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