[Haskell-beginners] Empty list

[Mike Meyer]

On Wed, Mar 25, 2015 at 8:55 AM, Shishir Srivastava <
shishir.srivastava at gmail.com> wrote:

> Hi,
>
> Can someone please explain why this results in error -
>
> [] `elem` [1,2,3]
>
> Shouldn't the empty set by definition be the element of all sets including
> a non-empty set ?
>

Norbert gave you the information about Lists and Data.Set, but you're wrong
about the properties of the empty set. The empty set is a SUBSET of all
sets. But it's only a MEMBER of supersets of {{}}.
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