c++ - How can Boost.Asio create a buffer object of size equal to the size of the array? -

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consider following lines (boost/c++):

char d1[128]; size_t bytes_transferred = sock.receive(boost::asio::buffer(d1));

the boost.asio documentation states buffer of size 128 created.

but how can boost determine size of array? i've read several questions, answer size of array cannot determined in c++.

there template specialization arrays size known @ compile time http://www.boost.org/doc/libs/1_60_0/doc/html/boost_asio/reference/buffer/overload7.html

template<     typename podtype,     std::size_t n> mutable_buffers_1 buffer(     podtype (&data)[n]);

in c++ 'char[5]', 'char[128]' , 'char*' different types compiler can take advantage of http://www.cplusplus.com/faq/sequences/arrays/sizeof-array/#cpp


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