Proposal: Data.Bool.implies

[Andreas Abel]

+1 Same opinion as Joachim.  --Andreas

On 18.01.2016 16:43, Joachim Breitner wrote:
> Hi,
>
> Am Montag, den 18.01.2016, 03:17 +0100 schrieb Niklas Hambüchen:
>> I propose to add to Data.Bool:
>>
>>      -- | Boolean implication.
>>      implies :: Bool -> Bool -> Bool
>>      implies True  x = x
>>      implies False _ = True
>>
>>      infix 4 `implies` -- same as (==)
>
> I’m +1 on the grounds that although I know that one of <= or => cuts
> it, it causes extra mental work to find out which (and annoyance to
> find out that it is the “wrong” one). Using a name is explicit and gets
> it right the first time.
>
> -1 on changing the order for Bool, it would just break too much code
> that relies on that in a fairly obscure way.
>
> +1 for making it right-associative, as implications are usually
> written.
>
> Undecided about ==>. It would be nice, but the conflict with quickcheck
> would be annoying. Leaning towards -1.
>
>
> Greetings,
> Joachim

-- 
Andreas Abel  <><      Du bist der geliebte Mensch.

Department of Computer Science and Engineering
Chalmers and Gothenburg University, Sweden

andreas.abel at gu.se
http://www2.tcs.ifi.lmu.de/~abel/