Class: Factbase::Absent

Inherits:

TermBase

• Object
• TermBase
• Factbase::Absent

Defined in:

lib/factbase/terms/absent.rb

Overview

Represents a term that evaluates to true if the specified operand is absent in the fact.

Instance Method Summary

• #evaluate(fact, _maps, _fb) ⇒ Boolean

  Evaluate term on a fact.

• #initialize(operands) ⇒ Absent constructor

  Constructor.

Methods included from TermShared

#to_s

Constructor Details

#initialize(operands) ⇒ Absent

Constructor.

Parameters:

• operands (Array) —

  Operands

# File 'lib/factbase/terms/absent.rb', line 12

def initialize(operands)
  super()
  @operands = operands
end

Instance Method Details

#evaluate(fact, _maps, _fb) ⇒ Boolean

Evaluate term on a fact.

Parameters:

• fact (Factbase::Fact) —

  The fact

• _maps (Array<Factbase::Fact>) —

  All maps available

• _fb (Factbase) —

  Factbase to use for sub-queries

Returns:

• (Boolean) —

  True if absent

# File 'lib/factbase/terms/absent.rb', line 22

def evaluate(fact, _maps, _fb)
  assert_args(1)
  _by_symbol(0, fact).nil?
end