Adding the number 1 to a set has no effect
python, python-3.x, set
Solution
>>> 1 == True
True
I believe your problem is that `1` and `True` are the same value, so 1 is "already in the set".
>>> st
{'a', True, 'Vanilla'}
>>> 1 in st
True
In mathematical operations `True` is itself treated as `1`:
>>> 5 + True
6
>>> True * 2
2
>>> 3. / (True + True)
1.5
Though True is a bool and 1 is an int:
>>> type(True)
<class 'bool'>
>>> type(1)
<class 'int'>
Because `1 in st` returns True, I think you shouldn't have any problems with it. It is a very strange result though. If you're interested in further reading, @Lattyware points to PEP 285 which explains this issue in depth.
Problem
I cannot add the integer number `1` to an existing set. In an interactive shell, this is what I am doing: ``` >>> st = {'a', True, 'Vanilla'} >>> st {'a', True, 'Vanilla'} >>> st.add(1) >>> st {'a', True, 'Vanilla'} # Here's the problem; there's no 1, but anything else works >>> st.add(2) >>> st {'a', True, 'Vanilla', 2} ``` This question was posted two months ago, but I believe it was misunderstood. I am using Python 3.2.3.