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+// Copyright (c) 2019 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_VECTOR_H
+#define BITCOIN_UTIL_VECTOR_H
+
+#include <initializer_list>
+#include <type_traits>
+#include <vector>
+
+/** Construct a vector with the specified elements.
+ *
+ * This is preferable over the list initializing constructor of std::vector:
+ * - It automatically infers the element type from its arguments.
+ * - If any arguments are rvalue references, they will be moved into the vector
+ * (list initialization always copies).
+ */
+template<typename... Args>
+inline std::vector<typename std::common_type<Args...>::type> Vector(Args&&... args)
+{
+ std::vector<typename std::common_type<Args...>::type> ret;
+ ret.reserve(sizeof...(args));
+ // The line below uses the trick from https://www.experts-exchange.com/articles/32502/None-recursive-variadic-templates-with-std-initializer-list.html
+ (void)std::initializer_list<int>{(ret.emplace_back(std::forward<Args>(args)), 0)...};
+ return ret;
+}
+
+/** Concatenate two vectors, moving elements. */
+template<typename V>
+inline V Cat(V v1, V&& v2)
+{
+ v1.reserve(v1.size() + v2.size());
+ for (auto& arg : v2) {
+ v1.push_back(std::move(arg));
+ }
+ return v1;
+}
+
+/** Concatenate two vectors. */
+template<typename V>
+inline V Cat(V v1, const V& v2)
+{
+ v1.reserve(v1.size() + v2.size());
+ for (const auto& arg : v2) {
+ v1.push_back(arg);
+ }
+ return v1;
+}
+
+#endif // BITCOIN_UTIL_VECTOR_H