std::find, std::list::remove/erase

[Dae]

Edit: Solved. I was using std::find incorrectly.

Hi, quick question. How do you get operator== working with std::find? I got it working for std::list::remove, but using std::find to grab the iterator to use for std::list::erase fails.

error: no match for ‘operator==’ in ‘__first.std::_List_iterator<_Tp>::operator* [with _Tp = klass, _Tp& = klass&]() == __val’

note: candidates are: bool klass::operator==(klass&)
note:                 bool klass::operator==(const klass&)
note:                 bool klass::operator==(klass&) const
note:                 bool klass::operator==(const klass&) const

stl_algo.h

  /// This is an overload used by find() for the Input Iterator case.
  template<typename _InputIterator, typename _Tp>
    inline _InputIterator
    __find(_InputIterator __first, _InputIterator __last,
	   const _Tp& __val, input_iterator_tag)
    {
      while (__first != __last && !(*__first == __val)) // error here
	++__first;
      return __first;
    }

So __val is klass&, and *__first is.. iterator dereferenced into klass&?

What's the problem then?

Thanks!

[laserlight]

You should show your code, not the code from the standard library. It looks like you did not declare your member operator== as a const member function.

[Dae]

You should show your code, not the code from the standard library. It looks like you did not declare your member operator== as a const member function.

Look at the candidates.

[laserlight]

Look at the candidates.

Right. Perhaps I should have asked instead: why are there so many versions of member operator==?

Good to see that you solved it yourself, but you really should have posted your own code. I am not interested in what the standard library implementation is because it is far less likely wrong than your code.

[Dae]

Right. Perhaps I should have asked instead: why are there so many versions of member operator==?

I wanted to make sure it wasn't a calling compatibility issue, and those are the 4 ways to define an equality between the exact same type. I've since removed 3 of them.

I know you're not interested in the STL. I threw it in there for easy access and reference. Showing you that code might trigger a case when one of you had this issue. I didn't have to post the operator== code because the interface is already shown in the error. It didn't occur to me to show the std::find code, but now I know.

Take it easy