anchor.diff:     ECHO /SCRIPTS [dir] Where to install scripts installed by rocks.
      ECHO                Default is TREE/bin.
      ECHO.
  -   ECHO /L             Install LuaRocks' own copy of Lua even if detected.
  +   ECHO /LV [version]  Lua version to use; either 5.1 or 5.2.
  +   ECHO                Default is 5.1
  +   ECHO /L             Install LuaRocks' own copy of Lua even if detected,
  +   ECHO                this will always be a 5.1 installation.
      ECHO                ^(/LUA, /INC, /LIB, /BIN cannot be used with /L^)
      ECHO /LUA [dir]     Location where Lua is installed - e.g. c:\lua\5.1\
      ECHO                This is the base directory, the installer will look
  
positive.code: SET FORCE_CONFIG=
  SET USE_MINGW=
  SET MKDIR=.\bin\mkdir -p
  SET LUA_LIB_NAMES=lua5.1.lib lua51.dll liblua.dll.a
  SET REGISTRY=OFF
  SET P_SET=FALSE
  
  
negative.code:       ECHO Cannot combine option /L with any of /LUA /BIN /LIB /INC
        GOTO ERROR
     )
     IF NOT [%LUA_VERSION%]==[5.1] (
        ECHO Bundled Lua version is 5.1, cannot install 5.2
        GOTO ERROR
     )
  )
  IF NOT [%LUA_VERSION%]==[5.1] (
     IF [%LUA_VERSION%]==[5.2] (
        SET LUA_LIB_NAMES=%LUA_LIB_NAMES:5.1=5.2%
        SET LUA_LIB_NAMES=%LUA_LIB_NAMES:51=52%
     ) ELSE (
        ECHO Bad argument: /LV must either be 5.1 or 5.2
        GOTO ERROR
     )
  )
  
  SET FULL_PREFIX=%PREFIX%\%VERSION%
  SET BINDIR=%FULL_PREFIX%
  SET LIBDIR=%FULL_PREFIX%
  SET LUADIR=%FULL_PREFIX%\lua
  SET INCDIR=%FULL_PREFIX%\include
  SET LUA_SHORTV=%LUA_VERSION:.=%
  
  REM ***********************************************************
  REM Detect Lua
  