C++ Lambdas

What are Lambdas

Lambda is a convenient way of defining an anonymous function right at the location where it's invoked or passed as an argument to a function.
How to write Lambdas

You write capture closure in [] then in () you write arguments for your function and then you write function body in {}
```
auto lambda = [](){ std::cout << "This is a lambda function" << std::endl; };
```
and then you can use it just as a normal function
```
auto lambda = [](){ std::cout << "This is a lambda function" << std::endl; };
lambda();
```
In capture closure you can specify the mode it captures everything from outside. = mode passes everything by value. & mode passes everything by reference. Nothing set in [] won't capture anything. variable_name passes specified variable only.
For example you have variable a set to 5 then you have lambda defined in variable and then you invoke that lambda in a for loop. The variable a will be captured by lambda if you will set mode to = or &.
```
int a = 5;
auto lambda = [=](int value) {std::cout << value << " " << a << std::endl;}; // a will be captured by value
 
for(int i = 0; i < 5; i++){ 
    // we have access to value of 'a' inside this scope
    lambda(i);
}
```

What are Lambdas