用stl algorithm代替for loop
https://blog.csdn.net/YyoulingL/article/details/84515924
outs.map(|x| x.m).collect()
boost::copy( outs | transformed([](auto x){return x->m;}),std::back_inserter(mouts))
std::transform(outs.begin(), outs.end(), std::back_inserter(mouts), [](auto x){return x->m;})
https://zhuanlan.zhihu.com/p/29438120
原文：https://www.cnblogs.com/cutepig/p/12804206.html