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copied!<p>There are a few issues:</p> <ul> <li>First, there's no need to use <code>wait()</code> since that's implied by <code>get()</code>. </li> <li>Either <code>list</code> or <code>vector</code> works fine with <code>push_back</code>. You give the wrong number of arguments to <code>list::insert</code>. The best is to use in-place construction with <code>emplace_back</code></li> <li>It also seems you should only do <code>.get()</code> once. Subsequent calls to <code>get()</code> yields <code>std::future_error</code> exception.</li> <li>The syntax you used for constructing the futures does not exist. The simplest way to do things like that is with a lambda as below.</li> </ul> <h2>Full example:</h2> <pre><code>// g++ -pthread -std=c++0x #include <iostream> #include <future> #include <list> struct X { X(int v) : mv(v) {} int mv; int max_value() const { return mv; } }; int main(){ std::list<std::future<int> > results; X x4(4); X x5(5); X x3(3); results.emplace_back(std::async(std::launch::async, [&x4](){ return x4.max_value();})); results.emplace_back(std::async(std::launch::async, [&x5](){ return x5.max_value();})); results.emplace_back(std::async(std::launch::async, [&x3](){ return x3.max_value();})); // for sure there's better ways to do this step, but for clarity: int best_value=0; for (auto &r : results){ auto this_value=r.get(); if (best_value < this_value) best_value = this_value; } std:: cout << best_value << std::endl; } </code></pre> <p>Since you use a shared pointer you could also make the lambda take the object by value,</p> <pre><code>std::shared_ptr<SomeT> some_obj= ... from somewhere... ; results.emplace_back( std::async( std::launch::async, [some_obj](){ return some_obs->max_value();} ) ); </code></pre>

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