[comment]: WIP - code is being refactored...
##General code organization of this pacakge
lib/src/ |- ... |- universe/ - how we represent the closed-world semantics of a program.
[comment]: TODO fill in the rest
[comment]: TODO rename universe => world [comment]: TODO consider merging feature.dart and use.dart
How we represent the closed-world semantics of a program.
universe/ |- feature.dart - Features that may be used in the program. Using a feature | pulls in special code that the compiler needs to support it. |- use.dart - Describes a use of an element (a method, a class) and how it | is used by the program.