streamable meta

CMakeLists.txt

@@ -1,6 +1,6 @@
 cmake_minimum_required(VERSION 3.20)
 include(cmake/color.cmake)
-set(BLT_VERSION 0.18.16)
+set(BLT_VERSION 0.18.17)
 set(BLT_TEST_VERSION 0.0.1)
 
 set(BLT_TARGET BLT)

include/blt/std/meta.h

@@ -21,6 +21,8 @@
 
 #include <blt/std/types.h>
 #include <utility>
+#include <type_traits>
+#include <ostream>
 
 namespace blt::meta
 {
@@ -56,6 +58,29 @@ namespace blt::meta
     template<typename Lambda>
     lambda_helper(Lambda) -> lambda_helper<Lambda, decltype(&Lambda::operator())>;
     
+    // https://stackoverflow.com/questions/66397071/is-it-possible-to-check-if-overloaded-operator-for-type-or-class-exists
+    template<class T>
+    class is_streamable
+    {
+        private:
+            template<typename Subs>
+            static auto test(int) -> decltype(std::declval<std::ostream&>() << std::declval<Subs>(), std::true_type())
+            {
+                return std::declval<std::true_type>();
+            }
+            
+            template<typename>
+            static auto test(...) -> std::false_type
+            {
+                return std::declval<std::false_type>();
+            }
+        
+        public:
+            static constexpr bool value = decltype(test<T>(0))::value;
+    };
+    
+    template<class T>
+    inline constexpr bool is_streamable_v = is_streamable<T>::value;
     
 }
 

libraries/parallel-hashmap

@@ -1 +1 @@
-Subproject commit 8a889d3699b3c09ade435641fb034427f3fd12b6
+Subproject commit d88c5e15079047777b418132ece5879e7c9aaa2b