diff --git a/test/float.cpp b/test/float.cpp
index 81b8c45d..0a94ab3c 100644
--- a/test/float.cpp
+++ b/test/float.cpp
@@ -1,12 +1,12 @@
 #include "../float.hpp"
 
 #include "../debug.hpp"
+#include "../types.hpp"
+
 #include <limits>
 
 using namespace std;
 
-#define elems(x) (sizeof(x) / sizeof(0[x]))
-
 
 void
 test_double (void) {
diff --git a/types.hpp b/types.hpp
index afee0e5a..dbbd9922 100644
--- a/types.hpp
+++ b/types.hpp
@@ -92,5 +92,9 @@ sign_cast (const typename sign_types<T>::with_sign v)
 }
 
 
+/// Returns the number of elements of a statically allocated array
+template <typename T, size_t N>  
+size_t elems(T (&)[N])
+    { return N; }
 
 #endif // __TYPES_HPP