diff --git a/include/kyosu/types/impl/arithmetic.hpp b/include/kyosu/types/impl/arithmetic.hpp
index 66dd6695..dc064d57 100644
--- a/include/kyosu/types/impl/arithmetic.hpp
+++ b/include/kyosu/types/impl/arithmetic.hpp
@@ -39,11 +39,14 @@ namespace kyosu::_
   {
     if constexpr(concepts::cayley_dickson<T> && concepts::cayley_dickson<U>)
     {
-      using type = as_cayley_dickson_t<T,U>;
-      auto parts = kumi::map([&](auto const& v, auto const& w) { return eve::if_else(m, v, w); }, t, f);
-
-      if constexpr(eve::simd_value<Mask>) return eve::as_wide_as_t<type,Mask>{parts};
-      else                                return type{parts};
+      using type  = as_cayley_dickson_t<T,U>;
+      using ret_t = std::conditional_t<eve::simd_value<Mask>, eve::as_wide_as_t<type,Mask>, type>;
+      constexpr eve::as<eve::element_type_t<type>> tgt = {};
+
+      return ret_t{ kumi::map ( [&](auto const& v, auto const& w) { return eve::if_else(m, v, w); }
+                              , kyosu::convert(t, tgt), kyosu::convert(f, tgt)
+                              )
+                  };
     }
     else if constexpr(concepts::cayley_dickson<T> && !concepts::cayley_dickson<U>)
     {
diff --git a/test/unit/function/if_else.cpp b/test/unit/function/if_else.cpp
new file mode 100644
index 00000000..bb55e6e6
--- /dev/null
+++ b/test/unit/function/if_else.cpp
@@ -0,0 +1,64 @@
+//======================================================================================================================
+/*
+  Kyosu - Complex Without Complexes
+  Copyright : KYOSU Contributors & Maintainers
+  SPDX-License-Identifier: BSL-1.0
+*/
+//======================================================================================================================
+#include <kyosu/kyosu.hpp>
+#include <test.hpp>
+
+TTS_CASE_WITH ( "Check behavior of if_else on scalar cayley-dickson"
+              , tts::bunch<kyosu::scalar_real_types>
+              , tts::generate(tts::randoms(-100,+100))
+              )
+<typename T>(T const& a0 )
+{
+  using e_t = typename T::value_type;
+  for(auto e : a0)
+  {
+    auto m = eve::is_odd(e);
+    TTS_EQUAL ( kyosu::if_else( m, kyosu::complex<e_t>(0,-e), kyosu::complex<e_t>(0, e))
+              , kyosu::complex<e_t>(0,m ? -e : e)
+              );
+
+    TTS_EQUAL ( kyosu::if_else(m, kyosu::quaternion<e_t>(0,-e,1,-2), kyosu::quaternion<e_t>(0,e,-1, 2))
+              , kyosu::quaternion<e_t>(0,m ? -e : e,m ? 1 : -1,m ? -2 : 2)
+              );
+
+    TTS_EQUAL ( kyosu::if_else( eve::is_odd(e)
+                              , kyosu::complex<e_t>(0,-e)
+                              , kyosu::quaternion<e_t>(0, e,-1,  2)
+                              )
+              , kyosu::quaternion<e_t>(0,m ? -e : e,m ? 0 : -1,m ? 0 : 2)
+              );
+    TTS_EQUAL ( kyosu::if_else( eve::is_odd(e)
+                              , kyosu::quaternion<e_t>(0,-e, 1, -2)
+                              , kyosu::complex<e_t>(0, e)
+                              )
+              , kyosu::quaternion<e_t>(0,m ? -e : e,m ? 1 : 0,m ? -2 : 0)
+              );
+  }
+};
+
+TTS_CASE_WITH ( "Check behavior of if_else on SIMD cayley-dickson"
+              , tts::bunch<kyosu::scalar_real_types>
+              , tts::generate(tts::randoms(-100,+100))
+              )
+<typename T>(T const& a0 )
+{
+  using e_t   = typename T::value_type;
+  using c_t   = kyosu::complex<e_t>;
+  using q_t   = kyosu::quaternion<e_t>;
+  using wc_t  = eve::wide<c_t>;
+  using wq_t  = eve::wide<q_t>;
+
+  for(auto e : a0)
+  {
+    auto m = eve::is_odd(e);
+    TTS_EQUAL(kyosu::if_else(m, wc_t(c_t(0,-e))     , wc_t(c_t(0,e)))     , wc_t(c_t(0,m ? -e : e)));
+    TTS_EQUAL(kyosu::if_else(m, wq_t(q_t(0,-e,1,-2)), wq_t(q_t(0,e,-1,2))), wq_t(q_t(0,m ? -e : e,m ? 1 : -1,m ? -2 : 2)));
+    TTS_EQUAL(kyosu::if_else(m, wc_t(c_t(0,-e))     , wq_t(q_t(0,e,-1,2))), wq_t(q_t(0,m ? -e : e,m ? 0 : -1,m ? 0 : 2)));
+    TTS_EQUAL(kyosu::if_else(m, wq_t(q_t(0,-e,1,-2)), wc_t(c_t(0, e)))    , wq_t(q_t(0,m ? -e : e,m ? 1 : 0,m ? -2 : 0)));
+  }
+};