Type of a condition, used in wait and broadcast

Create a condition. Implementation-wise, * a duppy task is created that will be used to select a * waiting computation, and resume it. * Thus, priority and s represents, resp., the priority * and scheduler used when running calling process' computation.

wait h m is a computation that: *

• Unlock mutex m
• Wait until Condition.signal c or Condition.broadcast c has been called
• Locks mutex m
• Returns unit

broadcast c is a computation that * resumes all computations waiting on c. It should * return immediately.

signal c is a computation that resumes one * computation waiting on c. It should return * immediately.