boost - C++ meaning of [ ] -


this question has answer here:

that's example of boosts asio. [this] mean? why []?

acceptor_.async_accept(socket_,     [this](boost::system::error_code ec)

it lambda expression used create function expression

[] capture list

a list of symbols can passed follows:

  • [a,&b] captured value , b captured reference.
  • [this] captures pointer value
  • [&] captures automatic variables mentioned in body of lambda reference
  • [=] captures automatic variables mentioned in body of lambda value
  • [] captures nothing

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