Are Python variables pointers? Or else, what are they?
identifier, pointers, python, variables
Solution
We call them references. They work like this
i = 5 # create int(5) instance, bind it to i
j = i # bind j to the same int as i
j = 3 # create int(3) instance, bind it to j
print i # i still bound to the int(5), j bound to the int(3)
Small ints are interned, but that isn't important to this explanation
i = [1,2,3] # create the list instance, and bind it to i
j = i # bind j to the same list as i
i[0] = 5 # change the first item of i
print j # j is still bound to the same list as i
Problem
Variables in Python are just pointers, as far as I know. Based on this rule, I can assume that the result for this code snippet: ``` i = 5 j = i j = 3 print(i) ``` would be `3`. But I got an unexpected result for me, and it was `5`. Moreover, my Python book does cover this example: ``` i = [1,2,3] j = i i[0] = 5 print(j) ``` The result would be `[5,2,3]`. What am I understanding wrong?