So I have a class with an attribute, say a, and I want to be able to modify it by using a method but I want that method to be reusable with other attributes.
Example:
class My_Class():
def __init__(self):
self.a = 0
self.b = 1
def add_one(self, x):
x = x + 1
def add_to_all(self):
self.add_one(self.a)
self.add_one(self.b)
with the code above I would expect:
adder = My_Class()
print(adder.a)
# 0
adder.add_to_all()
print(adder.a)
#1
this is not working and I am wondering how can do what I intend.
ChaGPT suggests:
class My_Class():
def __init__(self):
self.a = 0
self.b = 1
def add_one(self, x):
setattr(self, x, getattr(self, x) + 1)
def add_two(self):
self.add_one('a')
self.add_one('b')
which works, but I might as well create two methods:
def add_a(self):
self.a = self.a + 1
def add_b(self):
self.b = self.b + 1
and would duplicate code but in my opinion it would be cleaner (this case only adds 1 to a variable but in my real problem there are many variables and complex operations in each method, a and b).
Any idea if there is another way to implement this or sugestion of which option to use (chatGPT or duplicate methods)?
In Python, ints are immutable. When you run x += 1, Python doesn't modify the value in memory that x is pointing to—it just points x to a different value.
With that in mind, there are a couple of ways you can go about this implementation. The solution you got from ChatGPT is probably the most straightforward, but here's another way that works:
class My_Class:
def __init__(self):
self.values = [0, 1]
@property
def a(self):
return self.values[0]
@property
def b(self):
return self.values[1]
def add_to_all(self):
self.values = [val + 1 for val in self.values]
This also will accomplish what you're going for, although if you also want to be able to set the values for a & b (i.e. self.a = 3) you'll need to add setter methods as well.