Set = (function()
    local Set = __TS__Class("Set")
    Set.name = "Set"
    function Set.prototype.____constructor(self, values)
        self[Symbol.toStringTag] = "Set"
        self.size = 0
        self.nextKey = {}
        self.previousKey = {}
        if values == nil then
            return
        end
        local iterable = values
        if iterable[Symbol.iterator] then
            local iterator = iterable[Symbol.iterator](iterable)
            while true do
                local result = iterator:next()
                if result.done then
                    break
                end
                self:add(result.value)
            end
        else
            local array = values
            for ____, value in ipairs(array) do
                self:add(value)
            end
        end
    end
    function Set.prototype.add(self, value)
        local isNewValue = not self:has(value)
        if isNewValue then
            self.size = self.size + 1
        end
        if self.firstKey == nil then
            self.firstKey = value
            self.lastKey = value
        elseif isNewValue then
            self.nextKey[self.lastKey] = value
            self.previousKey[value] = self.lastKey
            self.lastKey = value
        end
        return self
    end
    function Set.prototype.clear(self)
        self.nextKey = {}
        self.previousKey = {}
        self.firstKey = nil
        self.lastKey = nil
        self.size = 0
        return
    end
    function Set.prototype.delete(self, value)
        local contains = self:has(value)
        if contains then
            self.size = self.size - 1
            local next = self.nextKey[value]
            local previous = self.previousKey[value]
            if next and previous then
                self.nextKey[previous] = next
                self.previousKey[next] = previous
            elseif next then
                self.firstKey = next
                self.previousKey[next] = nil
            elseif previous then
                self.lastKey = previous
                self.nextKey[previous] = nil
            else
                self.firstKey = nil
                self.lastKey = nil
            end
            self.nextKey[value] = nil
            self.previousKey[value] = nil
        end
        return contains
    end
    function Set.prototype.forEach(self, callback)
        for key in __TS__Iterator(
            self:keys()
        ) do
            callback(_G, key, key, self)
        end
    end
    function Set.prototype.has(self, value)
        return (self.nextKey[value] ~= nil) or (self.lastKey == value)
    end
    Set.prototype[Symbol.iterator] = function(self)
        return self:values()
    end
    function Set.prototype.entries(self)
        local nextKey = self.nextKey
        local key = self.firstKey
        return {
            [Symbol.iterator] = function(self)
                return self
            end,
            next = function(self)
                local result = {done = not key, value = {key, key}}
                key = nextKey[key]
                return result
            end
        }
    end
    function Set.prototype.keys(self)
        local nextKey = self.nextKey
        local key = self.firstKey
        return {
            [Symbol.iterator] = function(self)
                return self
            end,
            next = function(self)
                local result = {done = not key, value = key}
                key = nextKey[key]
                return result
            end
        }
    end
    function Set.prototype.values(self)
        local nextKey = self.nextKey
        local key = self.firstKey
        return {
            [Symbol.iterator] = function(self)
                return self
            end,
            next = function(self)
                local result = {done = not key, value = key}
                key = nextKey[key]
                return result
            end
        }
    end
    Set[Symbol.species] = Set
    return Set
end)()