From 95cccf8a4b392959c1fd7ec0647e04eb13880865 Mon Sep 17 00:00:00 2001
From: Sebastian Falbesoner <sebastian.falbesoner@gmail.com>
Date: Fri, 5 Mar 2021 14:33:41 +0100
Subject: util: introduce helper AnyPtr to access std::any instances

Co-authored-by: Russell Yanofsky <russ@yanofsky.org>
---
 src/util/system.h | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/src/util/system.h b/src/util/system.h
index 291f3f5541..29657e56e2 100644
--- a/src/util/system.h
+++ b/src/util/system.h
@@ -25,6 +25,7 @@
 #include <util/threadnames.h>
 #include <util/time.h>
 
+#include <any>
 #include <exception>
 #include <map>
 #include <optional>
@@ -500,6 +501,18 @@ inline void insert(std::set<TsetT>& dst, const Tsrc& src) {
     dst.insert(src.begin(), src.end());
 }
 
+/**
+ * Helper function to access the contained object of a std::any instance.
+ * Returns a pointer to the object if passed instance has a value and the type
+ * matches, nullptr otherwise.
+ */
+template<typename T>
+T* AnyPtr(const std::any& any) noexcept
+{
+    T* const* ptr = std::any_cast<T*>(&any);
+    return ptr ? *ptr : nullptr;
+}
+
 #ifdef WIN32
 class WinCmdLineArgs
 {
-- 
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