Re: [Boost-users] [PropertyTree] Using with std algorithms

Subject: Re: [Boost-users] [PropertyTree] Using with std algorithms
From: Robert Jones (robertgbjones_at_[hidden])
Date: 2011-05-20 02:47:49

On Thu, May 19, 2011 at 6:00 PM, Sebastian Redl <
sebastian.redl_at_[hidden]> wrote:

>
> On 19.05.2011, at 10:52, Robert Jones wrote:
>
> On Thu, May 19, 2011 at 5:24 PM, Sebastian Redl <
> sebastian.redl_at_[hidden]> wrote:
>
>>
>> On 19.05.2011, at 08:56, Robert Jones wrote:
>>
>> Hi All
>>
>> Is it possible and practical to use the put and get methods of
>> Boost.PropertyTree with std
>> algorithms?
>>
>> I've written this snippet, which doesn't compile, which I think is because
>> I have not correctly
>> expressed the return type of "put()". Is it possible to do this?
>>
>>
>> Yes, the put() overloads all return the affected tree node.
>>
>>     for_each( boost::begin( v ), boost::end( v ),
>>             bind( static_cast<void (ptree::*)( const std::string &,
>> unsigned )>( & ptree::put ), boost::ref( tree ), "Values.value", _1 ) );
>>
>>
>> Try this:
>>
>> static_cast<ptree& (ptree::*)(...)>
>>
>>
> Hi Sebstian
>
> Thanks for that, I thought that should work too, but seems there's still an
> overload problem!
>
> #include <algorithm>
> #include <vector>
> #include <boost/range.hpp>
> #include <boost/bind.hpp>
> #include <boost/property_tree/ptree.hpp>
>
> int main( )
> {
>     using boost::property_tree::ptree;
>
>      std::vector<unsigned> v;
>     ptree tree;
>
>     ptree & ( ptree::*myput )( const std::string &, unsigned ) = &
> ptree::put;
>
>
> The first argument should be a ptree::path_type (= string_path<char>), not
> std::string.
>
>
Hi Sebastian

YES! At last, it works. I had to change the last parameter to a const
reference too, but your strategy of
correctly matching the exact signature is the way to go.

Final code...

int main( )
{
    using boost::property_tree::ptree;

    std::vector<unsigned> v;
    ptree tree;

    ptree & ( ptree::*myput )( const ptree::path_type &, const unsigned & )
= & ptree::put;

    for_each( boost::begin( v ), boost::end( v ),
            bind( myput, boost::ref( tree ), "Values.value", _1 ) );
}

Many Thanks

- Rob.