Class: Roby::EventConstraints::UnboundTaskPredicate::SingleEvent

Inherits:
Roby::EventConstraints::UnboundTaskPredicate show all
Defined in:
lib/roby/event_constraints.rb

Overview

Subclass of UnboundTaskPredicate to handle single event generators

This is the class that is e.g. returned by UnboundPredicateSupport#to_unbound_task_predicate

Instance Attribute Summary collapse

Instance Method Summary collapse

Methods inherited from Roby::EventConstraints::UnboundTaskPredicate

#and, #compile, #evaluate, #negate, #or, #pretty_print, #to_unbound_task_predicate

Constructor Details

#initialize(event_name) ⇒ SingleEvent

Returns a new instance of SingleEvent.



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# File 'lib/roby/event_constraints.rb', line 769

def initialize(event_name)
    @event_name = event_name
    @required_events = [event_name].to_set
    super()
end

Instance Attribute Details

#event_name ⇒ Object (readonly)

The generator name as a symbol



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# File 'lib/roby/event_constraints.rb', line 764

def event_name
  @event_name
end

#required_events ⇒ Object (readonly)

The set of events required to compute this predicate. This is used by UnboundTaskPredicate#compile



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# File 'lib/roby/event_constraints.rb', line 767

def required_events
  @required_events
end

Instance Method Details

#==(pred) ⇒ Object 



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# File 'lib/roby/event_constraints.rb', line 775

def ==(pred); pred.kind_of?(SingleEvent) && pred.event_name == event_name end

#code ⇒ Object

Code generation to create the overall evaluated predicate



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# File 'lib/roby/event_constraints.rb', line 778

def code
    if @deadline
        return "task_#{event_name} && (task_#{event_name}.time.to_f > #{@deadline.to_f})"
    else
        "!!task_#{event_name}"
    end
end

#explain_false(task) ⇒ Object 



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# File 'lib/roby/event_constraints.rb', line 795

def explain_false(task)
    generator = task.event(event_name)
    if !generator.emitted?
        Explanation.new(false, self, [generator])
    end
end

#explain_static(task) ⇒ Object 



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# File 'lib/roby/event_constraints.rb', line 801

def explain_static(task)
    event = task.event(event_name)
    if event.last
        Explanation.new(true, self, [event.last])
    elsif event.unreachable?
        Explanation.new(nil, self, [event])
    end
end

#explain_true(task) ⇒ Object

Returns an Explanation object that explains why self is true. Note that it is valid only if evaluate(task) actually returned true (it will silently return an invalid explanation if evaluate(task) returns false).



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# File 'lib/roby/event_constraints.rb', line 790

def explain_true(task)
    if event = task.event(event_name).last
        Explanation.new(true, self, [event])
    end
end

#followed_by(event) ⇒ Object 



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# File 'lib/roby/event_constraints.rb', line 827

def followed_by(event)
    FollowedBy.new(self, event.to_unbound_task_predicate)
end

#from_now ⇒ Object 



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# File 'lib/roby/event_constraints.rb', line 818

def from_now
    @deadline = Time.now
    self
end

#never ⇒ Object 



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# File 'lib/roby/event_constraints.rb', line 814

def never
    Never.new(self)
end

#not_followed_by(event) ⇒ Object 



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# File 'lib/roby/event_constraints.rb', line 823

def not_followed_by(event)
    NotFollowedBy.new(self, event.to_unbound_task_predicate)
end

#static?(task) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/roby/event_constraints.rb', line 809

def static?(task)
    event = task.event(event_name)
    evaluate(task) || event.unreachable?
end

#to_s ⇒ Object 



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# File 'lib/roby/event_constraints.rb', line 831

def to_s; "#{event_name}?" end