Dave Thomas <Dave / thomases.com> writes:

>      [ 1, 2, 1 ] - [ 1 ]   # -> [2]
>      [ 1, 2, 1 ] - [ 2 ]   # -> [1]
> 
> I would have expected the result to be [ 1, 1 ].
> 
> Ah, you say, Array#- is _set_ difference, and a set can't contain
> duplicates.
> 
> Yes, I say, but
> 
>     [ 1, 2, 1 ] + [ 1, 2, 3 ] # -> [1, 2, 1, 1, 2, 3]

And then I said - heh Dave, why not read this telephone-directory
sized pile of paper that Andy and you just spent months putting
together, and lo!, I'm an idiot, as I forgot that '|' is set addition, 
and '+' is array concatenation, so '-' and '|' are the complementary
operators.


Sorry, folks, it's been a week of late nights. I should have locked
away the keyboard a long time ago.


Dave