11.7. Instances as Return ValuesΒΆ
Functions and methods can return objects. This is actually nothing new since everything in Python is an object and we have been returning values for quite some time. The difference here is that we want to have the method create an object using the constructor and then return it as the value of the method.
Suppose you have a point object and wish to find the midpoint halfway
between it and some other target point. We would like to write a
method, call it halfway
that takes another Point
as a
parameter and returns the Point
that is halfway between the point
and the target.
The resulting Point, mid
, has an x value of 4.0 and a y value of 8.0.
We can also use any other methods since mid
is a Point
object.
In the definition of the method halfway
see how the requirement to
always use dot notation with attributes disambiguates the meaning of
the attributes x
and y
: We can always see whether the
coordinates of Point self
or target
are being referred to.