Class: Comparability::Comparators::ComparatorChain

Inherits:
Comparability::Comparator show all
Extended by:
Forwardable
Includes:
Enumerable
Defined in:
lib/comparability/comparators/comparator_chain.rb

Instance Attribute Summary collapse

Instance Method Summary collapse

Methods inherited from Comparability::Comparator

#to_proc

Methods included from FactoryMethods

#chain, #create, #natural_order, #prioritize_nil, #reverse

Constructor Details

#initialize(comparators) ⇒ ComparatorChain

Returns a new instance of ComparatorChain.

Raises:

  • (ArgumentError) 


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# File 'lib/comparability/comparators/comparator_chain.rb', line 11

def initialize(comparators)
  raise ArgumentError unless comparators.size > 0
  raise ArgumentError unless comparators.all? { |c| c.is_a?(Comparator) }
  @comparators = comparators.freeze
end

Instance Attribute Details

#comparators ⇒ Object (readonly)

Returns the value of attribute comparators.



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# File 'lib/comparability/comparators/comparator_chain.rb', line 17

def comparators
  @comparators
end

Instance Method Details

#compare(me, other) ⇒ Object 



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# File 'lib/comparability/comparators/comparator_chain.rb', line 20

def compare(me, other)
  inject(0) do |zero, comparator|
    result = comparator.compare(me, other)
    if result.nil?
      # the comparator failed
      return nil
    elsif result.nonzero?
      # we have the conclusion
      return result
    else
      # a tie
      next 0
    end
  end
end