table.from = function(f)
	local tbl = {}
	local i = 1
	for v in f do
		tbl[i] = v
		i = i + 1
	end
	return tbl
end
table.max = function(t)
	local maxk, maxv
	if type(t) == "table" then
		for k,v in pairs(t) do
			if not maxk or maxv < v then
				maxk = k
				maxv = v
			end
		end
	else
		for k,v in t do
			if not maxk or maxv < v then
				maxk = k
				maxv = v
			end
		end
	end
	return maxk, maxv
end

table.min = function(t)
	local mink, minv
	if type(t) == "table" then
		for k,v in pairs(t) do
			if not mink or minv > v then
				mink = k
				minv = v
			end
		end
	else
		for k,v in t do
			if not mink or minv > v then
				mink = k
				minv = v
			end
		end
	end
	return mink, minv
end

table.find = function(t, f)
	if type(t) == "table" then
		for k,v in pairs(t) do
			if f(k,v) then
				return k,v
			end
		end
	else
		for k,v in t do
			if f(k,v) then
				return k,v
			end
		end
	end
end

table.filter = function(t, f)
	if type(t) == "table" then
		local it = nil
		return function()
			while true do
				it = next(t, it)
				if not it then
					break
				elseif f(it,t[it]) then
					return it,t[it]
				end
			end
		end
	else
		return function()
			while true do
				local k,v = t()
				if not k then
					break
				elseif f(k,v) then
					return k,v
				end
			end
		end
	end
end

table.map = function(t, f)
	if type(t) == "table" then
		local it = nil
		return function()
			it = next(t, it)
			if it then
				return f(it, t[it])
			end
		end
	else
		return function()
			local k,v = t()
			if k then
				return f(k,v)
			end
		end
	end
end