non-standard things in the gnu stl

[Uwe Sassenberg]

Concerns: STL
Details: std::set, std::multiset


To whom it may concern,

My name is Uwe Sassenberg at Science-D-Visions. I found out that the API 
of std::set and std::multiset are not as defined in the standard.
This is not a compiler problem, everything can be fixed within the 
header-file stl_set.h and stl_multiset.h. It would be fine to find out 
if the problem is already being solved by the gnu people.

Could you please tell me, with whom I should get into contact?
Thank you

Uwe Sassenberg

Here is a brief description of the problem:

------------8<------------

There is no difference in the definition of std::set<T>::iterator and 
std::set<T>::const_iterator. As a consequence, there is only a method

iterator begin() const;

but the Standard requires two methods

const_iterator begin() const;
iterator begin();

The same problem exists for end() as well.

If T contains two methods foo() and foo() const, only the
foo() const method can be accessed via the iterators.

------------8<------------

#include <set>
#include <iostream>

class X
	{
private:
	int _i;
public:
	X(int i):_i(i) { }
	void foo() const { std::cout << "foo() const" << std::endl; }
	void foo() { std::cout << "foo()" << std::endl; }
	bool operator < (const X& x) const { return _i < x._i; }
	};

void test(std::set<X>& s) { s.begin()->foo(); }

void test_const(const std::set<X>& s) { s.begin()->foo(); }

int main()
	{
	std::set<X> s;
	s.insert(X(1));
	test(s);
	test_const(s);
	}


Compile with   g++ -g test_set.C -o test_set

produces

foo() const
foo() const

but should produce

foo()
foo() const


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