xor operator?

[Tim Peters]

[Greg Wilson]
> LOL! I grepped through SmallEiffel's standard library and found one
> place where the boolean xor was used: in part of a contract.

[Nicola Musatti]
> And was it really more expressive than a (very probably) equivalent
> "!=" would have been?

In Eiffel, yes:  logical expressions play a much larger role in Eiffel than
in most other languages, and in some contexts are even auto-extracted into
the docs.  "A xor B" communicates "exactly one of A and B must hold" more
clearly than "whether A holds is not equal to whether B holds".  That's
important there.  Eiffel has an infix "implies" operator for the same
reason.

but-eiffel-isn't-python-ly y'rs  - tim