Three Recursively defined modules

[Isaac Dupree]

Chris Kuklewicz wrote:
> Can anyone see how to use hs-boot files to compile the three modules below?

I tried. I failed. I don't think it's possible if we 
restrict ourselves to adding {-#SOURCE#-} to the .hs files 
and adding .hs-boot files.  In any case it's not possible in 
all cases.  Which annoys me.

> It would be disappointing if I had to move the "key"s into separate modules/namespaces to allow for a solution using hs-boot files. 

I would suggest that this is actually not bad at all (more 
modules, more hs-boot files, what's the difference?). 
Except I realized, then you have orphan Show instances. 
What a nuisance.

-Isaac