Control parameters

[neighthan]

In the paper, you mention and show some examples of using control parameters, so I assume those should be supported with this library, but I'm having trouble getting them to parse. Here's a minimal example that's failing (using a durative action because the example in your paper did, so I'm not sure if you support control parameters on simple actions):

Domain

(define (domain test)

(:requirements :strips :fluents :durative-actions)

(:functions
  (x)
)

(:durative-action set_x
  :parameters ()
  :control (?x_new - number)
  :duration (= ?duration 1)
  :condition (and
    (at start (<= -1 ?x_new))
    (at start (<= ?x_new 1))
  )
  :effect (and
    (at end (assign (x) ?x_new))
  )
)

)

Problem

(define (problem test1) (:domain test)

(:init
  (= (x) 0)
)

(:goal (and
  (= (x) 1)
))
)

Error

Due to critical errors in the supplied domain/problem file, the planner
has to terminate.  The errors encountered are as follows:

Errors: 3, warnings: 0
/domain.pddl: line: 11: Error: Syntax error in durative-action declaration.
/domain.pddl: line: 11: Error: Unreadable structure
/domain.pddl: line: 12: Error: Syntax error in domain

(line 11 is the :control line)

How could I fix this file so the control parameter is parsed correctly?