Quick A: A compiler-generated type that stores the captured variables in its data members, and exposes the function signature and body as its operator().

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What type do lambdas get compiled into?

As I know all data types must be known at compile time, and lambda is not a type. Does lambda got translated into anonymous struct with operator() or std::function wrapped?

For example,

std::for_each(v.begin(), v.end(), [](int n&){n++;});