10 KiB
[func.wrap.copy.ctor]
22 General utilities library [utilities]
22.10 Function objects [function.objects]
22.10.17 Polymorphic function wrappers [func.wrap]
22.10.17.5 Copyable wrapper [func.wrap.copy]
22.10.17.5.3 Constructors, assignments, and destructor [func.wrap.copy.ctor]
template<class VT> static constexpr bool is-callable-from = see below;
If noex is true,is-callable-from is equal to:is_nothrow_invocable_r_v<R, VT cv ref, ArgTypes...> && is_nothrow_invocable_r_v<R, VT inv-quals, ArgTypes...>
Otherwise, is-callable-from is equal to:is_invocable_r_v<R, VT cv ref, ArgTypes...> && is_invocable_r_v<R, VT inv-quals, ArgTypes...>
copyable_function() noexcept; copyable_function(nullptr_t) noexcept;
Postconditions: *this has no target object.
copyable_function(const copyable_function& f);
Postconditions: *this has no target object if f had no target object.
Otherwise, the target object of *this is a copy of the target object of f.
Throws: Any exception thrown by the initialization of the target object.
May throw bad_alloc.
copyable_function(copyable_function&& f) noexcept;
Postconditions: The target object of *this is the target object f had before construction, andf is in a valid state with an unspecified value.
template<class F> copyable_function(F&& f);
Let VT be decay_t.
Constraints:
remove_cvref_t is not the same type as copyable_function, and
remove_cvref_t is not a specialization of in_place_type_t, and
is-callable-from is true.
Mandates:
is_constructible_v<VT, F> is true, and
is_copy_constructible_v is true.
Preconditions: VT meets the Cpp17Destructible andCpp17CopyConstructible requirements.
Postconditions: *this has no target object if any of the following hold:
f is a null function pointer value, or
f is a null member pointer value, or
remove_cvref_t is a specialization of the copyable_function class template, and f has no target object.
Otherwise, *this has a target object of type VT direct-non-list-initialized with std::forward(f).
Throws: Any exception thrown by the initialization of the target object.
May throw bad_alloc unless VT is a function pointer or a specialization of reference_wrapper.
template<class T, class... Args> explicit copyable_function(in_place_type_t<T>, Args&&... args);
Let VT be decay_t.
Constraints:
is_constructible_v<VT, Args...> is true, and
is-callable-from is true.
Mandates:
VT is the same type as T, and
is_copy_constructible_v is true.
Preconditions: VT meets the Cpp17Destructible andCpp17CopyConstructible requirements.
Postconditions: *this has a target object of type VT direct-non-list-initialized with std::forward(args)....
Throws: Any exception thrown by the initialization of the target object.
May throw bad_alloc unless VT is a pointer or a specialization of reference_wrapper.
template<class T, class U, class... Args> explicit copyable_function(in_place_type_t<T>, initializer_list<U> ilist, Args&&... args);
Let VT be decay_t.
Constraints:
is_constructible_v<VT, initializer_list&, Args...> istrue, and
is-callable-from is true.
Mandates:
VT is the same type as T, and
is_copy_constructible_v is true.
Preconditions: VT meets the Cpp17Destructible andCpp17CopyConstructible requirements.
Postconditions: *this has a target object of type VT direct-non-list-initialized withilist, std::forward(args)....
Throws: Any exception thrown by the initialization of the target object.
May throw bad_alloc unless VT is a pointer or a specialization of reference_wrapper.
copyable_function& operator=(const copyable_function& f);
Effects: Equivalent to: copyable_function(f).swap(*this);
Returns: *this.
copyable_function& operator=(copyable_function&& f);
Effects: Equivalent to: copyable_function(std::move(f)).swap(*this);
Returns: *this.
copyable_function& operator=(nullptr_t) noexcept;
Effects: Destroys the target object of *this, if any.
Returns: *this.
template<class F> copyable_function& operator=(F&& f);
Effects: Equivalent to: copyable_function(std::forward(f)).swap(*this);
Returns: *this.
~copyable_function();
Effects: Destroys the target object of *this, if any.