fun with smart constructors

if a test imports a public module, which imports a private module,
the linker fails on `cabal test` with "unknown symbol"

http://stackoverflow.com/questions/19739395/cant-compile-haskell-project-linking-step-fails
Haddock

"<...>" links can refer to local files

"-- |" comments are haddock documentation
fun with parsec
isolate orphan instances

still hurts modules' composeability, even if transitively imported (I think)
marshaling: map from VirtualKey to BitVector
Haddock
parse FilePath to Application

refactor parser to basename
fun with monadic failure

make smart constructor factory a total function
fun with total functions (safety hurts)
Makefile builds library / reinstalls package

executable imports module which can import library