util/bitcompat.lua

   1 -- Compatibility layer for bitwise operations
   2
   3 -- First try the bit32 lib
   4 -- Lua 5.3 has it with compat enabled
   5 -- Lua 5.2 has it by default
   6 if _G.bit32 then
   7         return _G.bit32;
   8 else
   9         -- Lua 5.1 may have it as a standalone module that can be installed
  10         local ok, bitop = pcall(require, "bit32")
  11         if ok then
  12                 return bitop;
  13         end
  14 end
  15
  16 do
  17         -- Lua 5.3 and 5.4 would be able to use native infix operators
  18         local ok, bitop = pcall(require, "util.bit53")
  19         if ok then
  20                 return bitop;
  21         end
  22 end
  23
  24 do
  25         -- Lastly, try the LuaJIT bitop library
  26         local ok, bitop = pcall(require, "bit")
  27         if ok then
  28                 return bitop;
  29         end
  30 end
  31
  32 error "No bit module found. See https://prosody.im/doc/depends#bitop";