🚀 go-pugleaf

I have run into a problem with the STL and Visual C++ 4, but I'm
not sure whether the C++ language definition, or the STL 
definition, or just Visual C++ itself is to blame.

I want to make a map of objects and key them on addresses. That's 
not an unreasonable request; a map of memory blocks keyed on their 
own addresses would be very useful if you wanted to concatenate them.

Here is a map declaration, using chars keyed on float addresses:

map< float*, char, less<float*> > theMap ;

Of course, when Microsoft get around to default template parameters, 
I will be able to omit the functor    less<float*>

Now, let's use one of the member functions of map, to insert
a char and its keying address; any address will illustrate

void f()

{

	float ff ;

	float* const pf = &ff ;

	theMap.insert( make_pair( pf, 'g' ) ) ;

}

This won't compile! The problem? the float address is not const, but 
the code in the map template requires a const key object, i.e. it
requires    pair< float* const, char >   

I have made pf a const float pointer, but that should not make a 
difference in any case as we are passing a value.

The first problem arises with the library function make_pair(). It 
takes const references to the objects you pass, but it returns a 
pair<> object containing NON-CONST ones. So, is the STL at fault?

The second problem arises with the compiler. Visual C++ will not
convert   pair< float* , char >    
to the required   pair< float* const, char >
That sounds reasonable to me, but again, is the compiler at fault?

Or does the definition of C++  ban that conversion, and of so, 
is IT right to do so?

How is it SUPPOSED to work? Any relevant thoughts would be appreciated.


          David
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