Java Script

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-- character table string local b='ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/'

-- encoding function enc(data) return ((data:gsub('.', function(x)

local r,b='',x:byte()

for i=8,1,-1 do r=r..(b%2^i-b%2^(i-1)>0 and '1' or '0') end

return r;

if (#x < 6) then return '' end

local c=0

for i=1,6 do c=c+(x:sub(i,i)=='1' and 2^(6-i) or 0) end

return b:sub(c+1,c+1)

-- decoding function dec(data) data = string.gsub(data, '[^'..b..'=]', '') return (data:gsub('.', function(x)

if (x == '=') then return '' end

local r,f='',(b:find(x)-1)

for i=6,1,-1 do r=r..(f%2^i-f%2^(i-1)>0 and '1' or '0') end

return r;

if (#x ~= 8) then return '' end

local c=0

for i=1,8 do c=c+(x:sub(i,i)=='1' and 2^(8-i) or 0) end

return string.char(c)

-- command line if not called as library if (arg ~= nil) then

local func = 'enc'

for n,v in ipairs(arg) do

if (n > 0) then

if (v == "-h") then print "base64.lua [-e] [-d] text/data" break

elseif (v == "-e") then func = 'enc'

elseif (v == "-d") then func = 'dec'

else print(_G[func](v)) end

end

end

module('base64',package.seeall)