add_library(system
  assignment.cpp
  component.cpp
  constraint.cpp
  edge.cpp
  effect.cpp
  expression_builder.cpp
  expression.cpp
  guard.cpp
  invariant.cpp
  location.cpp
  parser.cpp
  process.cpp
  resolver.cpp
  state.cpp
  system_builder.cpp
  system.cpp
  target.cpp
  task.cpp
  variable.cpp
  varset.cpp
  zone.cpp 
)