How to append string to existing value from a module

[mcmah309]

I came across this issue when trying to find a solution to

How To Extend Environment Variables In Modules?

How does one extend environment variables in a module? Say Have this config for home manager home.sessionVariables = { LD_LIBRARY_PATH="${pkgs.libglvnd}/lib"; }; and I want to extend the LD_LIBRARY_PATH path rather than overwrite it. LD_LIBRARY_PATH is defined in my configuration.nix and in other home manager modules as well.

Is there an effort/proposal to create a function like mkOrder that will treat Strings in different modules as mergeable?