1 files changed, 64 insertions, 14 deletions
diff --git a/include/yacppdic/detail/factory-impl.hpp b/include/yacppdic/detail/factory-impl.hpp
index 3deede2..c6da207 100644
--- a/include/yacppdic/detail/factory-impl.hpp
+++ b/include/yacppdic/detail/factory-impl.hpp
@@ -5,18 +5,19 @@
 namespace yacppdic
 {
 
-template <class Return, class... Args>
-Factory<Return(Args...)>::Factory(const Factory &factory) : _functor(factory._functor)
+template <typename Return, typename... Args>
+Factory<Return(Args...)>::Factory(const Factory &factory) noexcept
+	: _functor(factory._functor)
 {
 }
 
-template <class Return, class... Args>
+template <typename Return, typename... Args>
 Factory<Return(Args...)>::Factory(Factory &&factory) noexcept
 	: _functor(std::move(factory._functor))
 {
 }
 
-template <class Return, class... Args>
+template <typename Return, typename... Args>
 auto Factory<Return(Args...)>::operator=(Factory &&factory) noexcept
 	-> Factory<Return(Args...)> &
 {
@@ -24,7 +25,7 @@ auto Factory<Return(Args...)>::operator=(Factory &&factory) noexcept
 	return *this;
 }
 
-template <class Return, class... Args>
+template <typename Return, typename... Args>
 auto Factory<Return(Args...)>::operator=(std::nullptr_t) noexcept
 	-> Factory<Return(Args...)> &
 {
@@ -32,39 +33,88 @@ auto Factory<Return(Args...)>::operator=(std::nullptr_t) noexcept
 	return *this;
 }
 
-template <class Return, class... Args>
-Factory<Return(Args...)>::~Factory() = default;
-
-template <class Return, class... Args>
+template <typename Return, typename... Args>
 Factory<Return(Args...)>::operator bool() const noexcept
 {
 	return static_cast<bool>(_functor);
 }
 
-template <class Return, class... Args>
-auto Factory<Return(Args...)>::operator()(Args... args) const -> Return
+template <typename Return, typename... Args>
+auto Factory<Return(Args...)>::operator()(Args... args) const noexcept -> Return
 {
 	return _functor(std::forward<Args>(args)...);
 }
 
-template <class Return, class... Args>
+template <typename Return, typename... Args>
 auto Factory<Return(Args...)>::target_type() const noexcept -> const std::type_info &
 {
 	return _functor.target_type();
 }
 
-template <class Return, class... Args>
+template <typename Return, typename... Args>
 template <typename Tp>
 auto Factory<Return(Args...)>::target() noexcept -> Tp *
 {
 	return static_cast<Tp *>(_functor.template target<Tp>());
 }
 
-template <class Return, class... Args>
+template <typename Return, typename... Args>
 template <typename Tp>
 auto Factory<Return(Args...)>::target() const noexcept -> const Tp *
 {
 	return _functor.template target<Tp>();
 }
 
+template <typename Return, typename... Args>
+inline auto operator==(const Factory<Return(Args...)> &factory, std::nullptr_t) noexcept
+	-> bool
+{
+	return !factory;
+}
+
+template <typename Return, typename... Args>
+inline auto operator==(std::nullptr_t, const Factory<Return(Args...)> &factory) noexcept
+	-> bool
+{
+	return !factory;
+}
+
+template <typename Return, typename... Args>
+inline auto operator!=(const Factory<Return(Args...)> &factory, std::nullptr_t) noexcept
+	-> bool
+{
+	return static_cast<bool>(factory);
+}
+
+template <typename Return, typename... Args>
+inline auto operator!=(std::nullptr_t, const Factory<Return(Args...)> &factory) noexcept
+	-> bool
+{
+	return static_cast<bool>(factory);
+}
+
+} // namespace yacppdic
+
+template <typename Function>
+constexpr auto not_null(Function const & /*unused*/) -> bool
+{
+	return true;
+}
+
+template <typename Function>
+constexpr auto not_null(Function *function_ptr) -> bool
+{
+	return function_ptr;
+}
+
+template <typename Return, typename Class>
+constexpr auto not_null(Return Class::*method_ptr) -> bool
+{
+	return method_ptr;
+}
+
+template <typename Function>
+constexpr auto not_null(yacppdic::Factory<Function> const &factory) -> bool
+{
+	return !!factory;
 }