[boost] Re: String Algo bug.

From: Stefan Slapeta (stefan_nospam__at_[hidden])
Date: 2004-07-18 13:34:10

John Maddock wrote:
> There seems to be a bug in the string algorithm library that results in a
> valid container iterator being compared to a "singular" default constructed
> iterator: this operation is not supported by the iterator requirements

I'm not sure if I understand correctly what you mean, but the default 
constructed iterator is inteded to represent the past-the-end value.

> 
> And the actual problem I think is caused by (iter_find.hpp#98):
> 
> transform_iter_type itBegin=
> 
> make_transform_iterator(
> 
> find_iterator_type( begin(Input), InputEnd, Finder ),
> 
> copy_range_type());
> 
> 
> transform_iter_type itEnd=
> 
> make_transform_iterator(
> 
> find_iterator_type(), // end iterator is default constructed here!!
> 
> copy_range_type());
> 
> SequenceSequenceT Tmp(itBegin, itEnd); // assertion here

I didn't find out yet what it is (it takes some time to get STLPort 
running...), but it works for c strings and crashes for std::string (see 
the first two calls of the library in the split testcase). These and 
other lines were changed a few days ago to fix a bug that we found on 
default constructed iterators for c strings. Now it seems there are also 
troubles with std::strings...
The problem is that Pavol left for vacation.

> 
> There may be other occurances of course, 
> 

Yes, one a few lines below (iter_split) but not more.

Stefan