Functions are another type of variable in JavaScript (with some nuances of course). Creating a function within another function changes the scope of the function in the same way it would change the scope of a variable. This is especially important for use with closures to reduce total global namespace pollution. The functions defined within … Read more
The syntax for decorators with arguments is a bit different – the decorator with arguments should return a function that will take a function and return another function. So it should really return a normal decorator. A bit confusing, right? What I mean is: def decorator_factory(argument): def decorator(function): def wrapper(*args, **kwargs): funny_stuff() something_with_argument(argument) result = … Read more
>>> def sum(x, y): … def do_it(): … return x + y … return do_it … >>> a = sum(1, 3) >>> a <function do_it at 0xb772b304> >>> a() 4 Is this what you were looking for? It’s called a closure.
A closure occurs when a function has access to a local variable from an enclosing scope that has finished its execution. def make_printer(msg): def printer(): print(msg) return printer printer = make_printer(‘Foo!’) printer() When make_printer is called, a new frame is put on the stack with the compiled code for the printer function as a constant … Read more