Class: Factbase::When

Inherits:

TermBase

• Object
• TermBase
• Factbase::When

Defined in:

lib/factbase/terms/when.rb

Overview

It evaluates the operands based on a logical “when” operation.

Instance Method Summary

• #evaluate(fact, maps, fb) ⇒ Boolean

  Evaluate term on a fact.

• #initialize(operands) ⇒ When constructor

  Constructor.

Methods included from TermShared

#to_s

Constructor Details

#initialize(operands) ⇒ When

Constructor.

Parameters:

• operands (Array) —

  Operands

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

def initialize(operands)
  super()
  @operands = operands
  @op = :when
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 first operand is false OR both are true

# File 'lib/factbase/terms/when.rb', line 23

def evaluate(fact, maps, fb)
  assert_args(2)
  a = @operands[0]
  b = @operands[1]
  !a.evaluate(fact, maps, fb) || (a.evaluate(fact, maps, fb) && b.evaluate(fact, maps, fb))
end