More exports and utilities
Handle empty matcher in matcher-match-value
Update gestalt union and erasure to match current API
Correct type error
Mark newly-spawned process as initially runnable
A process may have exited before it gets checked in step-children.
Leftover from switch from vectors to lists.
Bring examples into line with new API
Improve gestalt-combine function; n-ary gestalt-union
Gestalt-based ground.rkt