EverySet: Set wrapper for using union types in a Set, using `toString` as a hashing function. Can only be used on type that can be stringified.

EverySet.elm

module EverySet
    exposing
        ( EverySet
        , empty
        , insert
        , isEmpty
        , member
        , remove
        )

import Set exposing (Set)


type alias EverySet =
    Set String


hash : a -> String
hash =
    toString


empty : EverySet
empty =
    Set.empty


isEmpty : EverySet -> Bool
isEmpty everySet =
    Set.isEmpty everySet


insert : a -> EverySet -> EverySet
insert item everySet =
    Set.insert (hash item) everySet


member : a -> EverySet -> Bool
member item everySet =
    Set.member (hash item) everySet


remove : a -> EverySet -> EverySet
remove item everySet =
    Set.remove (hash item) everySet