Re: [boost] Re: from enumerations to I/O streams

From: David Abrahams (abrahams_at_[hidden])
Date: 2000-10-27 08:13:36

----- Original Message -----
From: "Anton Gluck" <gluc_at_[hidden]>
To: <boost_at_[hidden]>
Sent: Friday, October 27, 2000 12:48 AM
Subject: Re: [boost] Re: from enumerations to I/O streams

> > Actually not. It's complaining that you're trying to bind a non-const
> > ifstream reference to a const ifstream object. It's a const-correctness
> > issue, and it's /my/ bug. I'm working on a fix. In the meantime, I think
the
> > best you can do is to arrange for a constructor which takes a pointer to
an
> > ifstream as a parameter. If you don't want to intrude on your class'
>
> I have tried adding a second constructor, but am still getting an error
> from py_cpp:
>
> d:\py_cpp/extclass.h(475) : error C2664: '__thiscall
> TextRecordIterator::TextRecordIterator(class
> std::basic_ifstream<char,struct std::char_traits<char> > &)' : cannot
> convert parameter 1 from 'class std::basic_ifstream<char,struct
> std::char_traits<char> > *const ' to 'class
std::basic_ifstream<char,struct
> std::char_traits<char> > &'
>
> Is this part of the same bug, since it again involves const and non-const
> binding?

Yes. Non-const reference parameters to constructors don't work (yet). Fixing
this involves finding a way around the infamous reference-to-reference bug
which works on MSVC, which apparently takes some doing. If you can arrange
for a non-const pointer in the interface in place of the reference, though,
you can use it from Python with the same interface.

-Dave