diff options
| -rw-r--r-- | common/aloptional.h | 38 |
1 files changed, 35 insertions, 3 deletions
diff --git a/common/aloptional.h b/common/aloptional.h index 443da0b4..a4b37212 100644 --- a/common/aloptional.h +++ b/common/aloptional.h @@ -34,9 +34,25 @@ public: if(mHasValue) al::uninitialized_move_n(std::addressof(*rhs), 1, std::addressof(mValue)); } - template<typename... Args> - explicit optional(in_place_t, Args&& ...args) - : mHasValue{true}, mValue{std::forward<Args>(args)...} + template<typename... Args, REQUIRES(std::is_constructible<T, Args...>::value)> + explicit optional(in_place_t, Args&& ...args) : mHasValue{true} + , mValue{std::forward<Args>(args)...} + { } + template<typename U, typename... Args, REQUIRES(std::is_constructible<T, std::initializer_list<U>&, Args...>::value)> + explicit optional(in_place_t, std::initializer_list<U> il, Args&& ...args) + : mHasValue{true}, mValue{il, std::forward<Args>(args)...} + { } + template<typename U=value_type, REQUIRES(std::is_constructible<T, U&&>::value && + !std::is_same<typename std::decay<U>::type, in_place_t>::value && + !std::is_same<typename std::decay<U>::type, optional<T>>::value && + std::is_constructible<U&&, T>::value)> + constexpr explicit optional(U&& value) : mHasValue{true}, mValue{std::forward<U>(value)} + { } + template<typename U=value_type, REQUIRES(std::is_constructible<T, U&&>::value && + !std::is_same<typename std::decay<U>::type, in_place_t>::value && + !std::is_same<typename std::decay<U>::type, optional<T>>::value && + !std::is_constructible<U&&, T>::value)> + constexpr optional(U&& value) : mHasValue{true}, mValue{std::forward<U>(value)} { } ~optional() { reset(); } @@ -69,6 +85,22 @@ public: } return *this; } + template<typename U=T, REQUIRES(std::is_constructible<T, U>::value && + std::is_assignable<T&, U>::value && + !std::is_same<typename std::decay<U>::type, optional<T>>::value && + (!std::is_same<typename std::decay<U>::type, T>::value || + !std::is_scalar<U>::value))> + optional& operator=(U&& rhs) + { + if(*this) + mValue = std::forward<U>(rhs); + else + { + ::new (std::addressof(mValue)) T{std::forward<U>(rhs)}; + mHasValue = true; + } + return *this; + } const T* operator->() const { return std::addressof(mValue); } T* operator->() { return std::addressof(mValue); } |