param woes

goal: group<T> for any type
	- also group<set<T>> etc

problem: parameterization is just syntactic
	- can have groups of different types
	- but can't have isomorphisms between groups of different types

attempted solution: have an unrestricted group<Any> base class that restricted versions extend
problem: scope explosion (6 or 20 million clauses)

final solution?: composition instead of inheritance
	- all Groups can only have Elems
	- Elems can optionally have anything attached as data

- i've come to realize that the efficiency of alloy programs is directly negatively correlated with code quality. 
- loosely speaking, good code is extensible and you can do a lot of things with it, and alloy works by trying every possible thing you could do with the code. 
- so it kinda makes sense
- having an extensible module and then restraining it in a using module only works so well, because you still get all the original clauses from the first module
- getting around this would require high-level reduction stage before the reduction to CNF