Jean-Louis Leroy <jll@skynet.be>

 > the mem_fun family of adapters and helper functions all work only with
 > non-const member functions, it seems. Why is it so?

An oversight. I expect the const versions will be added (as they already
are in some (most?) implementations.

 - Bjarne

Bjarne Stroustrup, AT&T Labs, http://www.research.att.com/~bs
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In article <EHJrDE.FH0@research.att.com>, Bjarne Stroustrup wrote:
> I expect the const versions will be added (as they already
> are in some (most?) implementations.

Neither the Visual C++ 5.0 nor the latest version of Kai C++ have them.

Jean-Louis Leroy
http://ourworld.compuserve.com/homepages/jl_leroy
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Hello,

the mem_fun family of adapters and helper functions all work only with
non-const member functions, it seems. Why is it so? `const' versions
seem
a good thing to have, especially for functions taking no argument. For
example:

    class person
        {
        public:
            string name() const;

        // ...
        };

    vector<person*> simpsons;
    // ...
    transform(simpsons.begin(), simpsons.end(),
        ostream_iterator<string>(cout, "\n"), mem_fun(&person::name));

I wrote a const_mem_fun family myself, but it seems that this omission
may discourage some people from using `const'.

Jean-Louis Leroy
http://ourworld.compuserve.com/homepages/jl_leroy


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