Python 2.7 quick reference |  |
Python 2.7 quick reference | |
If a class defines an .__iter__()
method, that method is called:
Whenever the built-in iter()
function is applied to an instance of the class.
In any situation where the instance is iterated
over, such as when it appears as the controlling
iterable of a for statement.
The calling sequence is:
def __iter__(self):
...
The return value must be an iterator. An iterator is any
object that has a .next() method that returns
the next value in the sequence, or raises StopIteration when the sequence is exhausted. For
more information, see Section 24.2, “Iterators: Values that can produce a sequence of
values”.