parse HTML by using Boost.PropertyTree

for https://teratail.com/questions/25158

Require boost. When you use VS-Solution file, please set Environment variable　$(BOOST_ROOT) and $(BOOST_LIB).

using C++11(constexpr, noexcept).

• Visual Studio 2015 Upadte 1
• Visual Studio 2015 Clang with Microsoft CodeGen clang3.7
• msys2 mingw clang++ 3.7.0
• msys2 mingw g++ 5.3.0

Watch Source.cpp.

const std::vector<std::wstring> result = html_extract(L"sample.html", L"div.inner");

call html_extract like this. First argument is filename to analyse. specify relative path from current directory. Secound argument is search key. The format is same as css's selector(See below).

Don't forget to call std::wcout.imbue before call html_extract when you want to use std::wcout.