What is lambda capture by value in C++?

Can you explain what lambda capture by value means in C++?

Sure! In C++, lambda capture by value means that the lambda function makes a copy of the variables from the surrounding scope.

What happens to the original variable when captured by value?

The original variable remains unchanged. The lambda works with its own copy, so modifications inside the lambda do not affect the original.

Can you give me an example of lambda capture by value?

Of course! Here's a simple example:

int x = 10;
auto lambda = [x]() { return x + 5; };
std::cout << lambda(); // Outputs 15

In this case, x is captured by value.

Are there any performance implications of capturing by value?

Yes, capturing by value can lead to performance overhead if the captured variables are large, as copies are made. It's often better to capture by reference in such cases.