Lambda capture as const reference?

Question

Is it possible to capture by const reference in a lambda expression?

I want the assignment marked below to fail, for example:

#include 

        

Answer 1

In c++14 using static_cast / const_cast:

[&best_string = static_cast(best_string)](const string& s)
{
    best_string = s; // fails
};

DEMO

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In c++17 using std::as_const:

[&best_string = std::as_const(best_string)](const string& s)
{
    best_string = s; // fails
};

DEMO 2