Added lua into the kitchen sink demo.

demo/docs/lua.lua

@@ -0,0 +1,36 @@
+--[[--
+num_args takes in 5.1 byte code and extracts the number of arguments
+from its function header.
+--]]--
+
+function int(t)
+	return t:byte(1)+t:byte(2)*0x100+t:byte(3)*0x10000+t:byte(4)*0x1000000
+end
+
+function num_args(func)
+	local dump = string.dump(func)
+	local offset, cursor = int(dump:sub(13)), offset + 26
+	--Get the params and var flag (whether there's a ... in the param)
+	return dump:sub(cursor):byte(), dump:sub(cursor+1):byte()
+end
+
+-- Usage:
+num_args(function(a,b,c,d, ...) end) -- return 4, 7
+
+-- Python styled string format operator
+local gm = debug.getmetatable("")
+
+gm.__mod=function(self, other)
+    if type(other) ~= "table" then other = {other} end
+    for i,v in ipairs(other) do other[i] = tostring(v) end
+    return self:format(unpack(other))
+end
+
+print([===[
+    blah blah %s, (%d %d)
+]===]%{"blah", num_args(int)})
+
+--[=[--
+table.maxn is deprecated, use # instead.
+--]=]--
+print(table.maxn{1,2,[4]=4,[8]=8) -- outputs 8 instead of 2