I have tried and errored a reasonable amount of times

[Chris Angelico]

On Fri, Sep 5, 2014 at 12:53 PM, Denis McMahon <denismfmcmahon at gmail.com> wrote:
> On Thu, 04 Sep 2014 21:42:56 +1000, Chris Angelico wrote:
>
>> On Thu, Sep 4, 2014 at 9:17 PM, Denis McMahon <denismfmcmahon at gmail.com>
>> wrote:
>>> On Wed, 03 Sep 2014 07:16:34 +0000, Steven D'Aprano wrote:
>>>
>>>> Who uses + for disjunction (∨ OR) and concatenation for conjunction (∧
>>>> AND)? That's crazy notation.
>>>
>>> The way I was taught it in the mid 1980s, a.b === a and b, a+b === a or
>>> b.
>>
>> The middle dot is another notation for multiplication, as is abuttal
>> (not actually concatenation, in this context). So they're all saying the
>> same thing: boolean 'and' is multiplication, boolean 'or' is addition.
>
> Yes Chris, I know that. I was responding to Stephen's statement that
> using + for or was crazy notation, and pointing out that 30 years ago,
> that's what UK colleges were teaching!

Ah, okay. Wasn't sure if you meant to be agreeing with multiplication
or offering an alternative.

ChrisA