@return [Conflict] a {Conflict} that reflects the failure to activate
the {#possibility} in conjunction with the current {#state}
@return [Array<Array<Object>>] The different requirement
trees that led to every requirement for the current spec.
Indicates progress roughly once every second @return [void]
Add the current {#possibility} to the dependency graph of the current {#state} @return [void]
This integer returns the current initial length of the buffer.
This sets the initial length of the buffer to length, if length > 0, otherwise its value isn’t changed.
Removes a possibility from ‘self` @return [PossibilityState] a state with a single possibility,
the possibility that was removed from `self`