Can I Move Elements from a `std::initializer_list`?

Can I Move Elements from std::initializer_list?

When using std::initializer_list, it's logical to believe that one can move elements out of it. However, the following code demonstrates otherwise:

#include <initializer_list>
#include <utility>

template<typename T>
void foo(std::initializer_list<T> list)
{
    for (auto it = list.begin(); it != list.end(); ++it)
    {
        bar(std::move(*it));   // Safe?
    }
}

Contrary to expectations, attempting to move elements out of std::initializer_list results in copies instead. This arises due to the unique nature of std::intializer_list, which requires special compiler handling and lacks the value semantics of typical containers.

The issue lies with the return type of begin() and end() for std::initializer_list, which is const T . Therefore, the expression 'std::move(it)' produces an immutable rvalue reference (T const &&&), which cannot be effectively moved from. It merely binds to a function parameter of type T const & because rvalues bind to const lvalue references, resulting in copy semantics.

This behavior may seem counterintuitive, but it allows the compiler to potentially make the initializer_list a statically-initialized constant. Nonetheless, it introduces an inconsistency where the user is left uncertain about whether the result of begin() and end() is const or mutable.

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