id	summary	reporter	owner	description	type	status	milestone	component	version	severity	resolution	keywords	cc
5710	ptree::sort() compilation error	bolero.murakami+cpp@…	Sebastian Redl	"It is an error code:

{{{
boost::property_tree::ptree pt;
pt.sort();
}}}


Output (VC9):
{{{
c:\program files\microsoft visual studio 9.0\vc\include\utility(103) : error C2784: 'bool std::operator <(const std::basic_string<_Elem,_Traits,_Alloc> &,const _Elem *)' : could not deduce template argument for 'const std::basic_string<_Elem,_Traits,_Alloc> &' from 'const boost::property_tree::basic_ptree<Key,Data>'
        with
        [
            Key=std::string,
            Data=std::string
        ]
        c:\program files\microsoft visual studio 9.0\vc\include\string(150) : see declaration of 'std::operator <'
        c:\program files\microsoft visual studio 9.0\vc\include\functional(143) : see reference to class template instantiation 'bool std::operator <<const Key,boost::property_tree::basic_ptree<Key,Data>>(const std::pair<_Ty1,_Ty2> &,const std::pair<_Ty1,_Ty2> &)' being compiled
        with
        [
            Key=std::string,
            Data=std::string,
            _Ty1=const std::string,
            _Ty2=boost::property_tree::basic_ptree<std::string,std::string>
        ]
        c:\program files\microsoft visual studio 9.0\vc\include\functional(142): while compiling class template member function 'bool std::less<_Ty>::operator ()(const _Ty &,const _Ty &) const' being compiled
        with
        [
            _Ty=std::pair<const std::string,boost::property_tree::basic_ptree<std::string,std::string>>
        ]
        ...
}}}


No-argument ptree::sort() in the element less<pair<const string, ptree> > to be compared by.

However, this comparison operators are not defined.　Therefore be a compilation error.

I think, the no-argument ptree::sort() should implemented by a comparison of key strings.
"	Bugs	closed	To Be Determined	property_tree	Boost 1.47.0	Problem	fixed