Align is_complex<T> implementation with STL wrappers of DPC++ compiler

Author: antonwolfy

dpctl/tensor/libtensor/include/utils/type_utils.hpp

@@ -35,13 +35,22 @@ namespace tensor
 namespace type_utils
 {
 
-template <class T> struct is_complex : std::false_type
+template <typename T, typename = void>
+struct is_complex : public std::false_type
 {
 };
-template <class T> struct is_complex<std::complex<T>> : std::true_type
+
+template <typename T>
+struct is_complex<T, std::enable_if_t<std::is_same_v<std::remove_cv_t<T>, std::complex<sycl::half>> ||
+                                      std::is_same_v<std::remove_cv_t<T>, std::complex<float>> ||
+                                      std::is_same_v<std::remove_cv_t<T>, std::complex<double>>>>
+    : public std::true_type
 {
 };
 
+template <typename T>
+constexpr bool is_complex_v = is_complex<T>::value;
+
 template <typename dstTy, typename srcTy> dstTy convert_impl(const srcTy &v)
 {
     if constexpr (std::is_same<dstTy, srcTy>::value) {