[Haskell-cafe] Data.Foldable.all and empty list

Tony Morris tonymorris at gmail.com
Tue Sep 29 22:54:12 UTC 2015

All the spiders in my hand are purple. There are no spiders in my hand.

On 30/09/15 07:33, Lana Black wrote:
> Hello,
> Is there any particular reason why the 'all' function returns True when
> supplied with an empty list (or any other foldable)? I'm aware that it
> is implemented via All monoid instance, my question is whether this
> behaviour is intentional or it can be considered a bug.
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