luarocks 3.8 install error?

[penguin84]

I've been trying to install luarocks but get an error when running luarocks.exe. I tried following the instruction that were shown, and it said it wrote variables.LUA_LIBDIR to what is the default path, but when I run luarocks again, it says LUA_LIBDIR not found. The same thing happens with variables.LUA_INCDIR.
Here is what I get: