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Ryan Haining I know the standard has an exception for extending the lifetime of temporary objects, which basically says that binding a const reference in a constructor doesn't extend the lifetime, but does that apply to literals as well? E.g: class C {
pri
Ryan Haining I know the standard has an exception for extending the lifetime of temporary objects, which basically says that binding a const reference in a constructor doesn't extend the lifetime, but does that apply to literals as well? E.g: class C {
pri
innocent bystander Imagine the following simplified code: #include <iostream>
void foo(const int& x) { do_something_with(x); }
int main() { foo(42); return 0; }
(1) Besides optimization, what happens when 42 is passed to foo? Does the compiler stick 42 somew
innocent bystander Imagine the following simplified code: #include <iostream>
void foo(const int& x) { do_something_with(x); }
int main() { foo(42); return 0; }
(1) Besides optimization, what happens when 42 is passed to foo? Does the compiler stick 42 somew
innocent bystander Imagine the following simplified code: #include <iostream>
void foo(const int& x) { do_something_with(x); }
int main() { foo(42); return 0; }
(1) Besides optimization, what happens when 42 is passed to foo? Does the compiler stick 42 somew
innocent bystander Imagine the following simplified code: #include <iostream>
void foo(const int& x) { do_something_with(x); }
int main() { foo(42); return 0; }
(1) Besides optimization, what happens when 42 is passed to foo? Does the compiler stick 42 somew
innocent bystander Imagine the following simplified code: #include <iostream>
void foo(const int& x) { do_something_with(x); }
int main() { foo(42); return 0; }
(1) Besides optimization, what happens when 42 is passed to foo? Does the compiler stick 42 somew
AND I'm trying to understand auto, but some questions confuse me. E.g: const int ci=0;
auto &g=ci;
auto &h=42;
Why is the second line correct and the third line wrong? Ayman Al Eliani You cannot have references or pointers to r values. An r-value is a value t
qiubit I'm creating a class with constructor initialization that const char*should safely construct an object using data provided in a buffer containing strings. My concern is that the user might NULLuse this constructor with the wrong data, e.g. a pointer or
Yongjian Wang 经验。我有一个 class foo{
public:
int const * const array;
size_t const length;
}
构造后这些变量不应该有任何变化，包括任何成员方法，但每个人都应该可以访问这些值，因此它们应该是常量。 但是在构造函数中，我需要先确定长度，然后才能初始化数组， 此外，我需要调用一个函数来分配内存位置，而不仅仅是一个new，因为这个类是一个巨大的不透明数据结构的桥梁，并且内存是由那个人管理的。（考虑诸如 v8
kelemat I know it's safe... const char *get_str_literal() {
return "I literally can't even";
}
But is it? const char *get_str_literal() {
const char *str = "I literally can't even";
return str;
}
If not, why? EDIT : How does the following differ
kelemat I know it's safe... const char *get_str_literal() {
return "I literally can't even";
}
But is it? const char *get_str_literal() {
const char *str = "I literally can't even";
return str;
}
If not, why? EDIT : How does the following differ
kelemat I know it's safe... const char *get_str_literal() {
return "I literally can't even";
}
But is it? const char *get_str_literal() {
const char *str = "I literally can't even";
return str;
}
If not, why? EDIT : How does the following differ
kelemat I know it's safe... const char *get_str_literal() {
return "I literally can't even";
}
But is it? const char *get_str_literal() {
const char *str = "I literally can't even";
return str;
}
If not, why? EDIT : How does the following differ
kelemat I know it's safe... const char *get_str_literal() {
return "I literally can't even";
}
But is it? const char *get_str_literal() {
const char *str = "I literally can't even";
return str;
}
If not, why? EDIT : How does the following differ
you don't know john I have an object created in a .h file which should be initialized in the constructor. In the current application, this object is passed a COM port number, which is 5. So I created a const int in the .h file. Edit: I added a more complete ex
Ryan Haining I've noticed strange semantics when binding references to pointers and arrays that differ in terms of constness to point and array elements, respectively. With pointers, this fails predictably: int* p{};
const int*& p_ref{p};
non-const lvalue ref
Lori E.g: #include <iostream>
#include <cstring>
using namespace std;
struct Square
{
Square()
{
str = new char[10];
strcpy(str, "Hello");
}
~Square()
{
delete str;
}
void print()
{
cout <<
Lori E.g: #include <iostream>
#include <cstring>
using namespace std;
struct Square
{
Square()
{
str = new char[10];
strcpy(str, "Hello");
}
~Square()
{
delete str;
}
void print()
{
cout <<
code_fodder Next comes this question: can a temporary lambda be passed by reference? I have a fixed code snippet: // global variable
std::thread worker_thread;
// Template function
template <typename Functor>
void start_work(const Functor &worker_fn) // lamb
code_fodder Next comes this question: can a temporary lambda be passed by reference? I have a fixed code snippet: // global variable
std::thread worker_thread;
// Template function
template <typename Functor>
void start_work(const Functor &worker_fn) // lamb
code_fodder Next comes this question: can a temporary lambda be passed by reference? I have a fixed code snippet: // global variable
std::thread worker_thread;
// Template function
template <typename Functor>
void start_work(const Functor &worker_fn) // lamb
moth Here is my function: const vector<int>& getVInt(){
vector<int> vint;
(...)
return vint;
}
and, vector<int> x = getVInt();
return: Throwing 'std:: out_of_range' what(): terminate call after vector::_M_range_check instance and const vector<int>& x
Bake ZQ Here is a subset of my code. Why can't a be bound const intto an rvalue reference? What I thought was that the type that Twould be deduced and the AS would be folded .int const &eint const & &&int const & template <typename T>
List<T>::List(initializer
Bake ZQ Here is a subset of my code. Why can't a be bound const intto an rvalue reference? What I thought was that the type that Twould be deduced and the AS would be folded .int const &eint const & &&int const & template <typename T>
List<T>::List(initializer
Bake ZQ Here is a subset of my code. Why can't a be bound const intto an rvalue reference? What I thought was that the type that Twould be deduced and the AS would be folded .int const &eint const & &&int const & template <typename T>
List<T>::List(initializer
Felix despised I am trying to pass the index obtained from the widget constructor to another page. But it doesn't work because the variable (index) I create in the constructor basically has no value. I understand. . But I don't know how to fix it. Any suggesti
gurga durgan I've seen a few things on these lines lately, and after a lot of searching, I haven't found an answer that directly addresses this issue. If I have the following code: class Foo {
const char *some_string;
Foo()
{
some_string =
gurga durgan I've seen a few things on these lines lately, and after a lot of searching, I haven't found an answer that directly addresses this issue. If I have the following code: class Foo {
const char *some_string;
Foo()
{
some_string =