value_type& value() const;
Requires: empty() == false. Returns: A reference to the
value_type subobject in the
container_node_type object pointed to by
ptr_. key_type& key() const;
Requires: empty() == false. Returns: A non-const reference to the
key_type member of the
value_type subobject in the
container_node_type object
pointed to by
ptr_. Remarks: Modifying the key through the returned reference is permitted
. mapped_type& mapped() const;
Requires: empty() == false. Returns: A reference to the
mapped_type member of the
value_type subobject in the
container_node_type object
pointed to by
ptr_. allocator_type get_allocator() const;
Requires: empty() == false. explicit operator bool() const noexcept;
Returns: ptr_ != nullptr. bool empty() const noexcept;
Returns: ptr_ == nullptr.