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I've been doing this for awhile now and this is the most confused I've been yet...what is the point of what he's doing? I've watched the video 3 times and I still have no clue what I'm even watching. Instead of age = 25, age+5=30...he's defining a class and within the class he's defining a method that adds? Then he's creating a NumString instance, which ends up as an int or float...and adding it to an int? What am I supposed to be taking away from this lesson?
Chris FreemanTreehouse Moderator 68,063 Points
The takeaway is not obvious. It's probably "if you create a class that you wish to use math on its instances, you'll need to create these math handling methods". This specific example of a string that can be operated upon with addition is as basic one can make. The idea being to show a simple non-math object that can be added.
Normal strings can be also added together, but only to other strings. Their
__add__ results in a new string through concatenation. Strings can be multiplied, but the
__mul__ method raises an error if the "other" is a non-
Another example, imagine a
Bookshelf class, where the
__add__ method added all the books from another
Bookshelf class to its own inventory.
__add__ methods add steps to do type checking and only allow adding to same type objects.
Post back if you need more help. Good Luck!