Make require check the LUA_PATH environment variable

[mcmanustfj]

Useful information to include:

• I want to be able to require("module") the module /modules/module.lua from programs/program.lua.

If there's something I'm missing that lets me do that already, lmk. /rom/modules is read only, so I can't put my own modules there

[SquidDev]

require looks up modules using the package.path, which by default looks in:

• Adjacent to the current program.
• /rom/modules.

So if your library is stored adjacent (or in a sub-folder) to your actual program, then you can still require it. Alternatively, you can extend the lookup path:

package.path = "/my/libs/?.lua;/my/libs/?/init.lua;" .. package.path

local lib = require "my_fancy_library" -- loads from /my/libs/my_fancy_library.lua

As far as persisting this sort of stuff, CC doesn't have environment variables, so LUA_PATH won't quite work! There have been discussions of other ways to do this (settings, shell API), but I'm not a fan of that approach.