问题
That's from an example of boosts asio. What does [this] mean? why the []?
acceptor_.async_accept(socket_,
[this](boost::system::error_code ec)
回答1:
It is a lambda expression used to create a function as an expression
[] is the capture list
A list of symbols can be passed as follows:
- [a,&b] where a is captured by value and b is captured by reference.
- [this] captures the this pointer by value
- [&] captures all automatic variables mentioned in the body of the lambda by reference
- [=] captures all automatic variables mentioned in the body of the lambda by value
- [] captures nothing
回答2:
It is a part of a lambda expression. Look here for more info.
来源：https://stackoverflow.com/questions/22327248/c-meaning-of