Questions tagged [copy-assignment]
146 questions
2
votes
3 answers
dynamic memory allocation,pointer members and destructors
I wrote the following dummy class to understand how the copy constructor,the copy assignment operator and the destructor works:
#include
#include
class Box {
public:
// default constructor
Box(int i=10,const…
Luca
- 1,658
- 4
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- 41
2
votes
1 answer
Generated copy and move operators?
Currently I read the book Effective Modern C++ from Scott Meyers, and now I'm at: Item 17: Understand special member function generation.
My misunderstanding comes from the following part (rationale):
The two copy operations are independent:…
p.i.g.
- 2,815
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- 41
2
votes
2 answers
thread-safe copy assignment operator for smart pointer class
I'm implementing a smart pointer class, and having a couple of confusions. Would really appreciate if people could help me clarify.
1: I thought smart pointer class should have "new" in constructor, "delete" in desctructor. But I can't seem to find…
Sarah
- 453
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2
votes
1 answer
Operator overloading "+" & "=" issue -- school asst
first time poster here but lurker for a couple of months now. Currently indulging in C++ with a small amount of Java knowledge as well from prior Comp Sci courses at school. I apologize if some of you look at this and are disappointed since there…
Gooeybanana
- 31
- 1
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1
vote
1 answer
Is there a Declarative approach to converting each member of a TypeScipt array to a full instance of an Object?
I have a class I can't change, simplified version shown. I got an array of variations on the class. I need to add the rest of the class to each member of the array before I can use them.
class ValueType {
name: string;
size: number = 5;
…
Scala Enthusiast
- 399
- 8
- 18
1
vote
1 answer
C++ implicitly declared move assignment operator calling implicitly declared copy assignment operator of base class
A simple question but I can not find the set of rules that proves that
the behavior of the following code example is correct. It seems here that only strDerived is
moved from b, but strBase is copied? Will the implicitly declared move assignment…
SoulfreezerXP
- 459
- 1
- 5
- 19
1
vote
1 answer
assigning a class variable outsite constructor body
I am very new to C++, and am following along with this tutorial and have come across this class constructor:
class Player: public Entity
{
private:
std::string m_Name;
public:
Player(const std::string& name)
: m_Name(name) {}
…
dg141
- 57
- 4
1
vote
3 answers
make template class with std::vector non-copyable when T is non-copyable
#include
#include
template
class V {
public:
template, int> = 0>
auto operator = (const V &rhs) -> V & { v = rhs.v; return *this; }
private:
…
slyx
- 2,063
- 1
- 19
- 28
1
vote
1 answer
Explicitly defaulted copy/move assignment operators implicitly deleted because field has no copy/move operators. C++
I'm new to C++ and dont know why this is happening and how to fix it. Here's some snippets of the code:
header file:
class Dictionary{
private:
string filename;
const string theSeparators;
public:
…
Coder-Me
- 13
- 3
1
vote
1 answer
Problem with my Copy and Move constructor and assignment operators
I want to build my own full Vector class in C++. I started like this:
#include
#include
#define Print(x)(std::cout<< x << std::endl)
// Vector Class //
template
class Vector
{
// Attributes
int…
DvB
- 41
- 3
1
vote
2 answers
How does the compiler copy member data that are arrays?
AFAIK, an array cannot be copied nor assigned so:
int a[5] = {1, 2};// 1 2 0 0 0
int b = a;// error
b = a; // error
But how does the compiler copies arrays that are member data of a class/struct type through the trivial copy-ctor and…
Itachi Uchiwa
- 3,044
- 12
- 26
1
vote
1 answer
C++ destructor called after calling constructor
By looking at the example:
#include
int wow=0;
class Foo{
int cow = 0;
public:
Foo(){
std::cout << "Foo +\n";
cow = 0;
++wow;
}
Foo(int n){
std::cout << "Foo has " << n << "\n";
cow = n;
++wow;
}
…
itchyfeet
- 43
- 7
1
vote
2 answers
Use copy constructor while user-declared move constructor is present
I'm having some confusion towards using the copy constructor and copy assignment operator while dealing with unique_ptr. I would really appreciate it if you could share some insights!
Now we have class B.
Struct C is a member of class B.
Struct C…
Skylar
- 127
- 8
1
vote
1 answer
Question about copy assignment and delete operator
I came across this link and I saw this program:
#include
template
class Auto_ptr4
{
T* m_ptr;
public:
Auto_ptr4(T* ptr = nullptr)
:m_ptr(ptr)
{
}
~Auto_ptr4()
{
delete m_ptr;
}
…
cuong.pq
- 137
- 1
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1
vote
1 answer
overloaded assignment operator not working
I have a class Employee. (Some of my comments are not updated from when I added members tasks and taskList; I apologize for that.)
Employee.h
#include
#include
using namespace std;
class Employee {
private:
string…
mostly_tired
- 45
- 3