local s_char = string.char;

local s_format = string.format;

local s_gsub = string.gsub;

local s_lower = string.lower;

local char_to_hex = {};

local hex_to_char = {};

do

	local char, hex;

	for i = 0,255 do

		char, hex = s_char(i), s_format("%02x", i);

		char_to_hex[char] = hex;

		hex_to_char[hex] = char;

	end

end

local function to(s)

	return (s_gsub(s, ".", char_to_hex));

end

local function from(s)

	return (s_gsub(s_lower(s), "%X*(%x%x)%X*", hex_to_char));

end

return { to = to, from = from }