75 questions
-1
votes
1
answer
98
views
Why does explicit default constructor prevent this from being constructed?
struct ExplicitDefaultConstructor
{
explicit ExplicitDefaultConstructor() {}
};
struct Material
{
ExplicitDefaultConstructor a;
int b;
};
int main() {
Material{.b = 2 };
}
It's ...
- 16.1k
3
votes
0
answers
67
views
conditional operator: inconsistency between implicit conversion sequence used for different compilers
This is a follow-up of this question: conditional operator expression with base and const derived class doesn't compile, why?.
The core is cond ? [cv] T1() : [cv] T2() where, for instance T2 ...
- 3,479
0
votes
2
answers
197
views
Why can't the constructor be called explicitly?
I was looking into creating a constructor to initialize an encapsulated std::array and came across a problem that the constructor of a copyable type (class A) could not be called explicitly. There are ...
0
votes
1
answer
47
views
How parameter type conversion in C++ operator works? [duplicate]
I am creating a new class VarDbl, which contains a few explicit constructors as well as a + operator:
class VarDbl {
...
explicit VarDbl(double value, double uncertainty);
explicit VarDbl(...
- 189
1
vote
1
answer
158
views
Is there any reason to mark a constructor of an abstract class as explicit
In the following example, my class is abstract due to the abstract method run. I also have a constructor from another type. I always mark constructor having only 1 argument as explicit, except when I ...
- 5,278
0
votes
0
answers
1k
views
error: use of deleted function operator=(&&) with std::optional
I got myself an error sprouting from std::optional. Now when trying to reconstruct it, there seems to be something going on with defaulted ctors that I don't yet understand. Consider the following ...
- 5,344
0
votes
1
answer
109
views
Why is there no implicit conversion sequence from int to vector<double>?
Regarding
vector<double> v2 = 9; //error: no conversion from int to vector
Is there no implicit conversion sequence of the copy-initialization from
int
to
vector<double>
because
std::...
- 464
9
votes
1
answer
219
views
Overload resolution between two constructors from std::initializer_list
In following program, struct C has two constructors : one from std::initializer_list<A> and the other from std::initializer_list<B>. Then an object of the struct is created with C{{1}}:
#...
- 24.1k
-1
votes
2
answers
1k
views
C++ copy assignment operator behaviour
I used the code below to test the behaviour of copy assignment operator:
#include <iostream>
using namespace std;
int group_number = 10; // Global
class Player {
public:
explicit Player(...
- 371
6
votes
1
answer
665
views
Why is my explicit constructor creating this ambiguity for my conversion operator?
I'm unable to figure out why my conversion operator is considering the explicit constructor.
#include <utility>
template <typename T = void>
struct First
{
template <typename... ...
- 707
3
votes
1
answer
225
views
Why is the converting constructor preferred to the conversion operator?
I have this class SmallInt that should represent a positive integer value in the range 0-255-inclusive:
struct SmallInt{
explicit SmallInt(int x = 0) : iVal_( !(x < 0 || x > 255) ? x :
...
- 3,214
1
vote
1
answer
259
views
Can't add element into container<T> with emplace new if T has explicit constructor
I am writing a fixed size container type, with placement new.
When I was testing it I figured it out my "emplace_back()" like function does not compile if the type T has explicit ctor.
Here ...
- 315
3
votes
2
answers
2k
views
C++ use of explicit suggested by cppcheck
Is using the cast constructor bad?
Otherweise why a code quality checker (cppcheck in my case) would constantly suggest to add explicit before single parameter constructors?
What if I want to do
class ...
- 2,480
0
votes
1
answer
2k
views
Is there really no explicit constructor of std::string from an std::string_view?
Some (many?) programmers who are introduced to both std::string_view and std::string ask themselves: "Why can I convert the latter into the former, but not the other way around?"
One part ...
- 137k
0
votes
0
answers
105
views
To use parameterized constructor through explicit call
I am facing an error while writing this code so here in the below program code the obj1 and obj2 are called explicitly by using parameterized constructor
But I am not able to get the output saying an ...
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