Re: [boost] [local] Help for the Alternatives section

Subject: Re: [boost] [local] Help for the Alternatives section
From: Michael Caisse (boost_at_[hidden])
Date: 2011-03-26 20:05:15

On 03/26/2011 04:46 PM, Steven Watanabe wrote:
> AMDG
>
> On 03/26/2011 04:27 PM, Michael Caisse wrote:
>> #include <boost/phoenix/phoenix.hpp>
>> #include <boost/phoenix/statement.hpp>
>> #include <iostream>
>> #include <vector>
>> #include <algorithm>
>>
>> int main() {
>>   double sum = 0.0;
>>   int factor = 10;
>>
>>   using namespace boost::phoenix;
>>   using namespace boost::phoenix::placeholders;
>>
>>   std::vector<double> v(3);
>>   v[0] = 1.0; v[1] = 2.0; v[2] = 3.0;
>>   std::for_each(v.begin(), v.end(), (
>>     ref(sum) += factor * _1,
>>     std::cout << "Summed: " << ref(sum) << "\n" )
>>   );
>>   return 0;
>> }
>>
>
> This is incorrect.  std::cout << "Summed: " is evaluated
> eagerly.
>
> In Christ,
> Steven Watanabe

Sorry about that:

     std::cout << val("Summed: ") << ref(sum) << "\n"

or one of the other possibilities will do fine.

michael

-- 
Michael Caisse
Object Modeling Designs
www.objectmodelingdesigns.com