Merge pull request #59 from GiovanniDicanio/optimize-regexpected-with…

…-move-ctor-overload Added Move-Semantics Constructor Overload in RegExpected
GiovanniDicanio · Jul 13, 2022 · ba6b749 · ba6b749
2 parents ef23e54 + 3d96d0f
commit ba6b749
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diff --git a/README.md b/README.md
@@ -1,4 +1,4 @@
-# WinReg v6.0.1
+# WinReg v6.1.0
 ## High-level C++ Wrapper Around the Low-level Windows Registry C-interface API
 
 by Giovanni Dicanio
@@ -106,9 +106,13 @@ You can also use the `RegKey::TryGet...Value` methods, that return `RegExpected<
 instead of throwing an exception on error:
 
 ```c++
+//
 // RegKey::TryGetDwordValue() returns a RegExpected<DWORD>;
-// the returned RegExpected contains a RegResult instance on error.
-
+// the returned RegExpected contains a DWORD on success, 
+// or a RegResult instance on error.
+//
+// 'res' is a RegExpected<DWORD> in this case:
+//
 const auto res = key.TryGetDwordValue(L"SomeDwordValue");
 if (res.IsValid())  // or simply:  if (res)
 {
@@ -129,7 +133,7 @@ else
 }
 ```
 
-**Version Note:** WinReg v5.1.1 is the latest version in which the `TryGetXxxValue` methods return 
+**Version Note** WinReg v5.1.1 is the latest version in which the `TryGetXxxValue` methods return 
 `std::optional<T>` (discarding the information about the error code).
 Starting from v6.0.0, the `TryGetXxxxValue` methods return `RegExpected<T>` (which keeps 
 the error information on failure).
@@ -149,4 +153,4 @@ The library stuff lives under the `winreg` namespace.
 See the [**`WinReg.hpp`**](WinReg/WinReg.hpp) header for more details and **documentation**.
 
 Thanks to everyone who contributed to this project with some additional features and constructive 
-comments and suggestions.
+comments and suggestions.
diff --git a/WinReg/WinReg.hpp b/WinReg/WinReg.hpp
@@ -71,7 +71,7 @@
 #include <memory>           // std::unique_ptr, std::make_unique
 #include <string>           // std::wstring
 #include <system_error>     // std::system_error
-#include <utility>          // std::swap, std::pair
+#include <utility>          // std::swap, std::pair, std::move
 #include <variant>          // std::variant
 #include <vector>           // std::vector
 
@@ -562,6 +562,10 @@ class RegExpected
     // Initialize the object with a value (the success case)
     explicit RegExpected(const T& value);
 
+    // Initialize the object with a value (the success case),
+    // optimized for move semantics
+    explicit RegExpected(T&& value);
+
     // Does this object contain a valid value?
     [[nodiscard]] explicit operator bool() const noexcept;
 
@@ -2777,6 +2781,12 @@ inline RegExpected<T>::RegExpected(const T& value)
 {}
 
 
+template <typename T>
+inline RegExpected<T>::RegExpected(T&& value)
+    : m_var{ std::move(value) }
+{}
+
+
 template <typename T>
 inline RegExpected<T>::operator bool() const noexcept
 {