Add math.log(number, [base])

math.lua

@@ -23,14 +23,22 @@ function sign(number)
 	if number > 0 then return 1 end
 end
 
-log = setmetatable({}, {__index = function(self, base)
+log = setmetatable({}, {
+	__index = function(self, base)
 		local div = math.log(base)
 		local function base_log(number)
 			return math.log(number) / div
 		end
 		self[base] = base_log
 		return base_log
-end})
+	end,
+	__call = function(_, number, base)
+		if not base then
+			return math.log(number)
+		end
+		return math.log(number) / math.log(base)
+	end
+})
 
 -- one-based mod
 function onemod(number, modulus)

test.lua

@@ -27,6 +27,8 @@ do
 	for i = -100, 100 do
 		local log = math.log[2](2^i)
 		assert(_G.math.abs(log - i) < 2^-40) -- Small tolerance for floating-point precision errors
+		assert(math.log(2^i) == _G.math.log(2^i))
+		assert(math.log(2^i, 2) == log)
 	end
 end