[fixed for bottom-posting]
Dr. Phillip M. Feldman wrote:
MRAB-2 wrote:
<snip>
What values should 'xor' return? IMHO, if only one of the values is true
then it should return that value, otherwise it should return False.
1 xor 0 => 1
0 xor 2 => 2
1 xor 2 => False
0 xor 0 => False
This is because it's a Boolean operator, so it should fall back to
Boolean values when necessary, like 'not':
not 0 => True
not 1 => False
Also:
x and y and z => (x and y) and z
x or y or z => (x or y) or z
therefore:
x xor y xor z => (x xor y) xor z
> Suppose that 'xor' returns the value that is true when only one value is
> true, and False otherwise. This definition of xor doesn't have the
standard
> associative property, that is,
>
> (a xor b) xor c
>
> will not necessarily equal
>
> a xor (b xor c)
>
> To see that this is the case, let a= 1, b= 2, and c= 3.
>
> (a xor b) xor c
>
> yields 3, while
>
> a xor (b xor c)
>
> yields 1. So, I'd prefer an xor operator that simply returns True or
False.
>
> Phillip
>
You are, of course, free to write your version however it makes sense to
you and your team. :)
Since the 'and' and 'or' already return objects (and objects evaluate to
true or false), then 'xor' should behave likewise, IMO. I expect that
would be the case if it were ever added to the language.
~Ethan~
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