Obtaining function pointer to lambda?

Question

I want to be able to obtain a function pointer to a lambda in C++.

I can do:

int (*c)(int) = [](int i) { return i; };

And, of cours

Answer 1

This fails:

auto *b = [](int i) { return i; };

because the lambda is not a pointer. auto does not allow for conversions. Even though the lambda is convertible to something that is a pointer, that's not going to be done for you - you have to do it yourself. Whether with a cast:

auto *c = static_cast([](int i){return i;});

Or with some sorcery:

auto *d = +[](int i) { return i; };