Augustus Saunders wrote:
Lambdas have no default constructor, which makes sense, as there would be no way to deal with the capture variables. So I'm wondering if anybody can shed some light on manually instantiating lambdas. I would think there is a way (possibly shady) to do this, at least for lambdas with no capture.
For lambdas with no capture, the following code might work: #include <iostream> int main (int argc, char* argv[]) { auto x = [](int i){ std::cout << i << std::endl; }; (*static_cast<decltype(x)*>(0))(5); return 0; } But, I strongly discourage its use. Instead, I recommend wrapping lambdas into boost::optional and constructing with in-place factories: #include <boost/optional.hpp> int main (int argc, char* argv[]) { auto x = [](int i){ return i * 100; }; // Store type and value in x boost::optional<decltype(x)> y; // Get type of x and default construct y y = boost::in_place(x); // Get value of x and lazily construct lambda return 0; } Regards, Michel