In programming, "pass by assignment" (also called "call by object reference" or "call by sharing") is a way of passing arguments to a function or method where the reference to the variable is passed instead of the actual value of the variable. This means that any changes made to the parameter variable inside the function will affect the original variable that was passed in.
For example, consider the following code snippet in Python:
def add_one(num): num += 1 return numx = 1print(add_one(x))print(x) |
In this code, we define a function add_one that takes a parameter num, increments it by one, and returns the result. We then create a variable x with the value 1, and call the add_one function with x as an argument.
The output of this code will be:
21 |
This is because add_one modifies the value of the num parameter inside the function, but does not affect the original value of x.
Pass by assignment can sometimes lead to unexpected results or bugs if the programmer is not aware of how it works. It is important to keep in mind that changes made to a parameter variable inside a function will affect the original variable that was passed in, and to use appropriate techniques such as copying or cloning variables if necessary to avoid unintended side effects.