[Tutor] question about operator overloading

[Alan Gauld]

On 06/03/12 02:42, Dave Angel wrote:

>> My guess would be similar to the cat operator in Unix:
>>
>> file3 = file1 + file2
>>
>
> So somehow assigning the object to file3 will write the data to a file
> by the name "file3" ? I know about __add__(), but didn't know we had
> __assign__()

We don't need any special assign behavior, its just standard Python 
assignment of the returned object to a name.

class MyFile(file):
....
    def __add__(self, file2):
       newFile = MyFile('foo.dat','wb')
       newFile.write(self.read())
       newFile.write(file2.read())
       return newFile

file3 = MyFile('spam.dat') + MyFile('baz.dat')

-- 
Alan G
Author of the Learn to Program web site
http://www.alan-g.me.uk/