Python Equality Check Difference

Question

Suppose we want some block of code to be executed when both \'a\' and \'b\' are equal to say 5. Then we can write like :

if a == 5 and b == 5:
    # do something         


        

Answer 1

It depends. You could write your own custom __eq__ which allows you to compare yourself to ints and things:

 class NonNegativeInt(object):
   def __init__(self, value):
     if value < 0:
       raise Exception("Hey, what the...")
     self.value = value

   def __eq__(self, that):
     if isinstance(that, int):
       return self.value == that
     elif isinstance(that, NonNegativeInt):
       return self.value == that.value
     else:
       raise ArgumentError("Not an acceptible argument", "__eq__", that)

which would work different depending on comparing "b" to "a" and "b" to an "int." Hence, a == b could be false while a == 5 and b == 5 could be True.