Reconsider the design of completePlan

[jfischoff]

Currently completePlan takes in a list environment variables. This makes it not possible to know what data directory is until the plan is complete. This makes creating a cache plan complicated.

I think we should revisit this decision.

[jfischoff]

So the issue is that I don't want defaultConfig to be defaultConfig :: IO Config vs defaultConfig :: Config. I also want to expand the environment variables for the Plan so I can see them.

The issue is that if I want to be able to create a cache config from an existing config I need to use IO then.

Which means I can't <> cacheConfig onto my config. Not sure what is worse.

[jfischoff]

As it stands now the complexity is internal. If I change the design I move the complexity onto the user. Sounds worse.

[jfischoff]

I think using unsafePerformIO to make a currentEnv var might be the best option.

The default just specifies it.