This page is a snapshot from the LWG issues list, see the Library Active Issues List for more information and the meaning of NAD status.
Section: 28.6.2.7 [valarray.cassign] Status: NAD Submitter: Gabriel Dos Reis Opened: 1999-08-15 Last modified: 2016-01-28
Priority: Not Prioritized
View all other issues in [valarray.cassign].
View all issues with NAD status.
Discussion:
26.5.2.6 defines augmented assignment operators valarray<T>::op=(const T&), but fails to provide corresponding versions for the helper classes. Thus making the following illegal:
#include <valarray>
int main()
{
std::valarray<double> v(3.14, 1999);
v[99] *= 2.0; // Ok
std::slice s(0, 50, 2);
v[s] *= 2.0; // ERROR
}
I can't understand the intent of that omission. It makes the valarray library less intuitive and less useful.
Rationale:
Although perhaps an unfortunate design decision, the omission is not a defect in the current standard. A future standard may wish to add the missing operators.