On 17/10/2015 01:45 PM, Orchid Win7 v1 wrote:
> Well, it turns out you can have *multiple guards* on a single expression!
>
>   case list of
>     [x, y, z] | x > 0, y > 0, z > 0 -> ...
>
> What does that even *do*?! <read the spec/> OK, so it seems it's the
> logical-AND of all the conditions? So, um, why not just write it as an AND?

I've been a Haskell programmer for [at least] 10 years, and I've never 
seen *anybody* do this!

...it turns out there's a reason for that. This is actually a *new* 
language feature, added in the Haskell 2010 specification.

Let me say that again: Somebody thought this was a *good* idea. They 
actually *added* this. On purpose.

So while the Haskell 2010 spec removed the much-hated N+K patterns 
misfeature, they've added something arguably even worse as well. <sigh>

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