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Kohei Ashida
4,882 PointsWhy is there str(value) in the first def
Kenneth has written the first def in the NumString class like
class NumString:
def __init__(self, value):
self.value = str(value)
def __str__(self):
return self.value
def __int__(self):
return int(self.value)
def __float__(self):
return float(self.value)
but why should str(value) be put in the first def? I thought it should be like below lines.
class NumString:
def __init__(self, value):
self.value = value #str() removed
def __str__(self):
return str(self.value) #str() added
def __int__(self):
return int(self.value)
def __float__(self):
return float(self.value)
What are advantages in writing like Kenneth did?
2 Answers
Steven Parker
229,744 PointsThe purpose of the class is to store numeric values as strings. The modification in the second example would cause it to store the value as a number, but convert it into a string on demand. To complete the modification, you'd need to make changes to the other methods as well.
Technically, the functionality could be reproduced the other way, but if the main intention of the class is to hold a value as a string, only the first example accomplishes that.
Kohei Ashida
4,882 PointsThanks so much, Steven! I forgot that Kenneth explained that it's to store numeric values as strings as you mentioned.