C++ constructor specialization using SFINAE
0
I have a templated struct whose member type depends on the specialization:
template<typename T>
struct Base
{
typedef T VT[4];
}
template<>
struct Base<float>
{
typedef ___m128 VT;
} // And other similar specializations for int, uint etc...
template<typename T>
struct A
{
typename A<T>::VT data;
}
I would like to specialize the copy constructor for pointer and non-pointer types:
// Non-pointer
A::A(const A & a) : data(a.data) { }
// Pointer
A::A(const A & a) { memcpy(data, a.data, sizeof(data)); }
I tried using a combination of std::enable_if and std::is_pointer but I cannot seem to make it work. Can someone show me how it's done?
c++ templates constructor sfinae template-specialization
asked Nov 23 '18 at 9:07
SneppySneppy
92211
add a comment |
0
I have a templated struct whose member type depends on the specialization:
template<typename T>
struct Base
{
typedef T VT[4];
}
template<>
struct Base<float>
{
typedef ___m128 VT;
} // And other similar specializations for int, uint etc...
template<typename T>
struct A
{
typename A<T>::VT data;
}
I would like to specialize the copy constructor for pointer and non-pointer types:
// Non-pointer
A::A(const A & a) : data(a.data) { }
// Pointer
A::A(const A & a) { memcpy(data, a.data, sizeof(data)); }
I tried using a combination of std::enable_if and std::is_pointer but I cannot seem to make it work. Can someone show me how it's done?
c++ templates constructor sfinae template-specialization
asked Nov 23 '18 at 9:07
SneppySneppy
92211
Have a look at stackoverflow.com/questions/29430090/…, may be a duplicate.
– Matthieu Brucher
Nov 23 '18 at 9:09
@Matthieu I think I did (in the sense that I'm not sure whether I did that correctly or not) but the compiler gave me a redefined error on the constructor
– Sneppy
Nov 23 '18 at 9:11
Then perhaps share your trials so that we can figure out the issue with your constructor.
– Matthieu Brucher
Nov 23 '18 at 9:12
Ok sorry, I'll edit my question as soon as I get my hands on the computer. That link you posted talks about conditionally disabling the copy constructor, which is not what I want, but I'll give it a look to see if it applies to my case too
– Sneppy
Nov 23 '18 at 9:17
add a comment |
0
0
0
I have a templated struct whose member type depends on the specialization:
template<typename T>
struct Base
{
typedef T VT[4];
}
template<>
struct Base<float>
{
typedef ___m128 VT;
} // And other similar specializations for int, uint etc...
template<typename T>
struct A
{
typename A<T>::VT data;
}
I would like to specialize the copy constructor for pointer and non-pointer types:
// Non-pointer
A::A(const A & a) : data(a.data) { }
// Pointer
A::A(const A & a) { memcpy(data, a.data, sizeof(data)); }
I tried using a combination of std::enable_if and std::is_pointer but I cannot seem to make it work. Can someone show me how it's done?
c++ templates constructor sfinae template-specialization
asked Nov 23 '18 at 9:07
SneppySneppy
92211
I have a templated struct whose member type depends on the specialization:
template<typename T>
struct Base
{
typedef T VT[4];
}
template<>
struct Base<float>
{
typedef ___m128 VT;
} // And other similar specializations for int, uint etc...
template<typename T>
struct A
{
typename A<T>::VT data;
}
I would like to specialize the copy constructor for pointer and non-pointer types:
// Non-pointer
A::A(const A & a) : data(a.data) { }
// Pointer
A::A(const A & a) { memcpy(data, a.data, sizeof(data)); }
I tried using a combination of std::enable_if and std::is_pointer but I cannot seem to make it work. Can someone show me how it's done?
c++ templates constructor sfinae template-specialization
c++ templates constructor sfinae template-specialization
asked Nov 23 '18 at 9:07
SneppySneppy
92211
asked Nov 23 '18 at 9:07
SneppySneppy
92211
asked Nov 23 '18 at 9:07
SneppySneppy
92211
asked Nov 23 '18 at 9:07
SneppySneppy
92211
asked Nov 23 '18 at 9:07
SneppySneppy
92211
92211
Have a look at stackoverflow.com/questions/29430090/…, may be a duplicate.
– Matthieu Brucher
Nov 23 '18 at 9:09
@Matthieu I think I did (in the sense that I'm not sure whether I did that correctly or not) but the compiler gave me a redefined error on the constructor
– Sneppy
Nov 23 '18 at 9:11
Then perhaps share your trials so that we can figure out the issue with your constructor.
– Matthieu Brucher
Nov 23 '18 at 9:12
Ok sorry, I'll edit my question as soon as I get my hands on the computer. That link you posted talks about conditionally disabling the copy constructor, which is not what I want, but I'll give it a look to see if it applies to my case too
– Sneppy
Nov 23 '18 at 9:17
add a comment |
Have a look at stackoverflow.com/questions/29430090/…, may be a duplicate.
– Matthieu Brucher
Nov 23 '18 at 9:09
@Matthieu I think I did (in the sense that I'm not sure whether I did that correctly or not) but the compiler gave me a redefined error on the constructor
– Sneppy
Nov 23 '18 at 9:11
Then perhaps share your trials so that we can figure out the issue with your constructor.
– Matthieu Brucher
Nov 23 '18 at 9:12
Ok sorry, I'll edit my question as soon as I get my hands on the computer. That link you posted talks about conditionally disabling the copy constructor, which is not what I want, but I'll give it a look to see if it applies to my case too
– Sneppy
Nov 23 '18 at 9:17
Have a look at stackoverflow.com/questions/29430090/…, may be a duplicate.
– Matthieu Brucher
Nov 23 '18 at 9:09
Have a look at stackoverflow.com/questions/29430090/…, may be a duplicate.
– Matthieu Brucher
Nov 23 '18 at 9:09
@Matthieu I think I did (in the sense that I'm not sure whether I did that correctly or not) but the compiler gave me a redefined error on the constructor
– Sneppy
Nov 23 '18 at 9:11
@Matthieu I think I did (in the sense that I'm not sure whether I did that correctly or not) but the compiler gave me a redefined error on the constructor
– Sneppy
Nov 23 '18 at 9:11
Then perhaps share your trials so that we can figure out the issue with your constructor.
– Matthieu Brucher
Nov 23 '18 at 9:12
Then perhaps share your trials so that we can figure out the issue with your constructor.
– Matthieu Brucher
Nov 23 '18 at 9:12
Ok sorry, I'll edit my question as soon as I get my hands on the computer. That link you posted talks about conditionally disabling the copy constructor, which is not what I want, but I'll give it a look to see if it applies to my case too
– Sneppy
Nov 23 '18 at 9:17
Ok sorry, I'll edit my question as soon as I get my hands on the computer. That link you posted talks about conditionally disabling the copy constructor, which is not what I want, but I'll give it a look to see if it applies to my case too
– Sneppy
Nov 23 '18 at 9:17
add a comment |
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Have a look at stackoverflow.com/questions/29430090/…, may be a duplicate.
– Matthieu Brucher
Nov 23 '18 at 9:09
@Matthieu I think I did (in the sense that I'm not sure whether I did that correctly or not) but the compiler gave me a redefined error on the constructor
– Sneppy
Nov 23 '18 at 9:11
Then perhaps share your trials so that we can figure out the issue with your constructor.
– Matthieu Brucher
Nov 23 '18 at 9:12
Ok sorry, I'll edit my question as soon as I get my hands on the computer. That link you posted talks about conditionally disabling the copy constructor, which is not what I want, but I'll give it a look to see if it applies to my case too
– Sneppy
Nov 23 '18 at 9:17