整理

include/boost/core/pointer_in_range.hpp

@@ -0,0 +1,49 @@
+/*
+Copyright 2024 Glen Joseph Fernandes
+(glenjofe@gmail.com)
+
+Distributed under the Boost Software License, Version 1.0.
+(http://www.boost.org/LICENSE_1_0.txt)
+*/
+#ifndef BOOST_CORE_POINTER_IN_RANGE_HPP
+#define BOOST_CORE_POINTER_IN_RANGE_HPP
+
+#include <boost/config.hpp>
+#include <functional>
+
+#if !defined(BOOST_NO_CXX14_CONSTEXPR)
+#if defined(BOOST_MSVC) && BOOST_MSVC >= 1925
+#define BOOST_CORE_DETAIL_HAS_IS_CONSTEVAL
+#elif defined(__has_builtin)
+#if __has_builtin(__builtin_is_constant_evaluated)
+#define BOOST_CORE_DETAIL_HAS_IS_CONSTEVAL
+#endif
+#endif
+#endif
+
+#if !defined(BOOST_CORE_DETAIL_HAS_IS_CONSTEVAL)
+#define BOOST_CORE_NO_CONSTEXPR_POINTER_IN_RANGE
+#endif
+
+namespace boost {
+
+template<class T>
+inline BOOST_CONSTEXPR bool
+pointer_in_range(const T* p, const T* b, const T* e)
+{
+#if defined(BOOST_CORE_DETAIL_HAS_IS_CONSTEVAL)
+    if ( __builtin_is_constant_evaluated()) {
+        for (; b != e; ++b) {
+            if (b == p) {
+                return true;
+            }
+        }
+        return false;
+    }
+#endif
+    return std::less_equal<const T*>()(b, p) && std::less<const T*>()(p, e);
+}
+
+} /* boost */
+
+#endif