From 0897ec126cba2cb89db24eec30c73c099f6222fe Mon Sep 17 00:00:00 2001
From: jyxiong <jingyu.xiong@foxmail.com>
Date: Mon, 22 Sep 2025 19:02:33 +0800
Subject: [PATCH] feat: add reference type traits

---
 .../composite_type_categories/is_reference.h        | 12 ++++++++++++
 .../primary_type_categories/is_lvalue_reference.h   | 13 +++++++++++++
 .../primary_type_categories/is_rvalue_reference.h   | 13 +++++++++++++
 3 files changed, 38 insertions(+)
 create mode 100644 source/tinystl/type_traits/composite_type_categories/is_reference.h
 create mode 100644 source/tinystl/type_traits/primary_type_categories/is_lvalue_reference.h
 create mode 100644 source/tinystl/type_traits/primary_type_categories/is_rvalue_reference.h

diff --git a/source/tinystl/type_traits/composite_type_categories/is_reference.h b/source/tinystl/type_traits/composite_type_categories/is_reference.h
new file mode 100644
index 0000000..a049922
--- /dev/null
+++ b/source/tinystl/type_traits/composite_type_categories/is_reference.h
@@ -0,0 +1,12 @@
+#pragma once
+
+#include "tinystl/type_traits/primary_type_categories/is_lvalue_reference.h"
+#include "tinystl/type_traits/primary_type_categories/is_rvalue_reference.h"
+
+namespace tinystl {
+template<class T>
+struct is_reference : bool_constant<is_lvalue_reference<T>::value || is_rvalue_reference<T>::value> {};
+
+template <class T>
+inline constexpr bool is_reference_v = is_reference<T>::value;
+}
\ No newline at end of file
diff --git a/source/tinystl/type_traits/primary_type_categories/is_lvalue_reference.h b/source/tinystl/type_traits/primary_type_categories/is_lvalue_reference.h
new file mode 100644
index 0000000..67593d9
--- /dev/null
+++ b/source/tinystl/type_traits/primary_type_categories/is_lvalue_reference.h
@@ -0,0 +1,13 @@
+#pragma once
+
+#include "tinystl/type_traits/helper_classes/integral_constant.h"
+
+namespace tinystl {
+template<class T>
+struct is_lvalue_reference : false_type {};
+template<class T>
+struct is_lvalue_reference<T&> : true_type {};
+
+template<class T>
+inline constexpr bool is_lvalue_reference_v = is_lvalue_reference<T>::value;
+}
\ No newline at end of file
diff --git a/source/tinystl/type_traits/primary_type_categories/is_rvalue_reference.h b/source/tinystl/type_traits/primary_type_categories/is_rvalue_reference.h
new file mode 100644
index 0000000..7885e79
--- /dev/null
+++ b/source/tinystl/type_traits/primary_type_categories/is_rvalue_reference.h
@@ -0,0 +1,13 @@
+#pragma once
+
+#include "tinystl/type_traits/helper_classes/integral_constant.h"
+
+namespace tinystl {
+template<class T>
+struct is_rvalue_reference : false_type {};
+template<class T>
+struct is_rvalue_reference<T&&> : true_type {};
+
+template <class T>
+inline constexpr bool is_rvalue_reference_v = is_rvalue_reference<T>::value;
+}
\ No newline at end of file