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diff --git a/src/util/overloaded.h b/src/util/overloaded.h
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+// Copyright (c) 2021 The Bitcoin Core developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#ifndef BITCOIN_UTIL_OVERLOADED_H
+#define BITCOIN_UTIL_OVERLOADED_H
+
+namespace util {
+//! Overloaded helper for std::visit. This helper and std::visit in general are
+//! useful to write code that switches on a variant type. Unlike if/else-if and
+//! switch/case statements, std::visit will trigger compile errors if there are
+//! unhandled cases.
+//!
+//! Implementation comes from and example usage can be found at
+//! https://en.cppreference.com/w/cpp/utility/variant/visit#Example
+template<class... Ts> struct Overloaded : Ts... { using Ts::operator()...; };
+
+//! Explicit deduction guide (not needed as of C++20)
+template<class... Ts> Overloaded(Ts...) -> Overloaded<Ts...>;
+} // namespace util
+
+#endif // BITCOIN_UTIL_OVERLOADED_H