From d825285a4a41916a0f952b9f53cba3edf0097fdb Mon Sep 17 00:00:00 2001
From: _Redstone_c_ <myredstone1024@gmail.com>
Date: Sun, 8 Jan 2023 18:03:05 +0800
Subject: [PATCH] feat(typetraits): add CDerivedFrom and the corresponding
 testing

---
 Redcraft.Utility/Source/Private/Testing/TypeTraitsTesting.cpp | 4 ++++
 Redcraft.Utility/Source/Public/TypeTraits/Miscellaneous.h     | 1 +
 2 files changed, 5 insertions(+)

diff --git a/Redcraft.Utility/Source/Private/Testing/TypeTraitsTesting.cpp b/Redcraft.Utility/Source/Private/Testing/TypeTraitsTesting.cpp
index bef5256..ce2a98f 100644
--- a/Redcraft.Utility/Source/Private/Testing/TypeTraitsTesting.cpp
+++ b/Redcraft.Utility/Source/Private/Testing/TypeTraitsTesting.cpp
@@ -322,6 +322,10 @@ void TestTypeTraits()
 	always_check(!(CConvertibleTo<FTestStructE*, FTestStructH*>));
 	always_check((CConvertibleTo<FTestStructW, FTestStructV>));
 
+	always_check(!(CDerivedFrom<FTestStructD, FTestStructH>));
+	always_check(!(CDerivedFrom<FTestStructE, FTestStructH>));
+	always_check((CDerivedFrom<FTestStructH, FTestStructE>));
+
 	always_check((CSameAs<int32, TRemoveConst<int32>>));
 	always_check(!(CSameAs<int32, TRemoveConst<int32*>>));
 	always_check(!(CSameAs<int32, TRemoveConst<int32&>>));
diff --git a/Redcraft.Utility/Source/Public/TypeTraits/Miscellaneous.h b/Redcraft.Utility/Source/Public/TypeTraits/Miscellaneous.h
index db539a8..afbe446 100644
--- a/Redcraft.Utility/Source/Public/TypeTraits/Miscellaneous.h
+++ b/Redcraft.Utility/Source/Public/TypeTraits/Miscellaneous.h
@@ -31,6 +31,7 @@ template <typename T, size_t I = 0> inline constexpr size_t TExtent =  NAMESPACE
 template <typename T, typename U> concept CSameAs        = NAMESPACE_STD::is_same_v<T, U>;
 template <typename T, typename U> concept CBaseOf        = NAMESPACE_STD::is_base_of_v<T, U>;
 template <typename T, typename U> concept CConvertibleTo = NAMESPACE_STD::is_convertible_v<T, U>;
+template <typename T, typename U> concept CDerivedFrom   = CBaseOf<U, T> && CConvertibleTo<const volatile T*, const volatile U*>;
 
 template <typename T> using TRemoveConst      = NAMESPACE_STD::remove_const_t<T>;
 template <typename T> using TRemoveVolatile   = NAMESPACE_STD::remove_volatile_t<T>;