Re: [boost] associative_vector: request for formal review

From: Darin Adler (darin_at_[hidden])
Date: 2000-05-30 12:54:01

on 5/30/00 10:48 AM, jsiek_at_[hidden] at jsiek_at_[hidden] wrote:
> template <class X, class Y>
> struct tied
> {
>     tied(X& x, Y& y) : m_x(x), m_y(y) {}
> 
>     template <class T1, class T2>
>     void operator=(const std::pair<T1,T2>& p)
>         { m_x = p.first; m_y = p.second; }
>     mutable X& m_x;
>     mutable Y& m_y;
> };

What does the "mutable" accomplish here? I think that you can modify objects
through m_x and m_y regardless of whether the tied object is const or not.
For reference members, it seems that mutable is a no-op.

    -- Darin