This is my second day of learning python (I know the basics of C++ and some OOP.), and I have some slight confusion regarding variables in python.
Here is how I understand them currently:
Python variables are references (or pointers?) to objects (which are either mutable or immutable). When we have something like
num = 5, the immutable object
5 is created somewhere in memory, and the name-object reference pair
num is created in a certain namespace. When we have
a = num, nothing is being copied, but now both variables refer to the same object and
a is added to the same namespace.
This is where my book, Automate the boring stuff with Python, confuses me. As it's a newbie book, it doesn't mention objects, namespaces, etc., and it attempts to explain the following code:
>>> spam = 42 >>> cheese = spam >>> spam = 100 >>> spam 100 >>> cheese 42
The explanation it offers is exactly the same as that of a C++ book, which I am not happy about as we are dealing with references/pointers to objects. So in this case, I guess that in the 3rd line, as integers are immutable,
spam is being assigned an entirely new pointer/reference to a different location in memory, i.e. the memory that it was initially pointing to wasn't modified. Hence we have
cheese referring to the initial object referred to by
spam. Is this the correct explanation?