awesome crashes after LUA_PATH change

[tastyminerals]

I have installed torch package and after the installation LUA_PATH was changed.

Here is my current $LUA_PATH

'/home/tastyminerals/.luarocks/share/lua/5.1/?.lua;/home/tastyminerals/.luarocks/share/lua/5.1/?/init.lua;/home/tastyminerals/torch/install/share/lua/5.1/?.lua;/home/tastyminerals/torch/install/share/lua/5.1/?/init.lua;./?.lua;/home/tastyminerals/torch/install/share/luajit-2.1.0-beta1/?.lua;/usr/local/share/lua/5.1/?.lua;/usr/local/share/lua/5.1/?/init.lua'

When I attempt to run awesome with startx it crashes complaining about not found lgi lib which is installed into /usr/lib/lua/5.3/lgi/ and other dirs. What lgi files/dirs does awesome need in order to start so that I could add the missing paths to $LUA_PATH?

[Elv13]

https://www.reddit.com/r/awesomewm/comments/4ljzhe/black_screen/

Lua versions are not compatible. If you try to run Awesome linked against 5.1 with liblua 5.3, it will crash. There is a workaround in the reddit link

[psychon]

Let me rewrite what you said and perhaps you see the problem:

I installed some shitty program which changed my LUA_PATH. Now the path that LGI is installed to is no longer found via LUA_PATH and so LGI is no longer found.

The answer is "your installation is broken, fix it". If you cannot run lua -e 'require("lgi")' successfully, then the problem is not with awesome.

And to help with this non-awesome-related problem:
Try unset LUA_PATH ; unset LUA_CPATH ; lua -e 'print(package.path) print(package.cpath)' to get the default values for LUA_PATH and LUA_CPATH (assuming torch broke your system by exporting these two variables, if it did other stupidity, you'd have to undo that as well).

P.S.: How come so many people started breaking their system with torch recently? I also saw a similar report recently on IRC. How come the guys behind torch do something as stupid as this?

[psychon]

I sent this bug report where it belongs: https://github.com/torch/distro/issues/120

[tastyminerals]

@psychon I think it has to do more the fact that different lua versions are incompatible, seriously lua needs a version manager.

[psychon]

I think debian manages to do that fine...

[tastyminerals]

So, the problem (in my case) can be prevented by commenting out the following line in .bashrc:
. /home/tastyminerals/torch/install/bin/torch-activate.

[ibrahima]

Just so you know, Torch is a popular library for scientific computing and machine learning, one that Facebook AI Research uses a lot. I just broke my awesome installation due to this same thing, thankfully I found the logs pointing me in the right direction. But yeah, this is definitely a torch issue, it'd be nice if their installer detected existing versions of Lua and didn't install the activation script in the case that lua was already installed.