Class: Nelson::Expression

Inherits:
Object
  • Object
show all
Defined in:
lib/nelson/expression.rb

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(*terms) ⇒ Expression

Returns a new instance of Expression.

Raises:

  • (ArgumentError) 


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# File 'lib/nelson/expression.rb', line 6

def initialize(*terms)
  raise ArgumentError, "At least 1 term must be specified" unless terms.length > 0
  @terms = terms
end

Instance Attribute Details

#terms ⇒ Object

Returns the value of attribute terms.



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# File 'lib/nelson/expression.rb', line 4

def terms
  @terms
end

Instance Method Details

#*(term) ⇒ Object 



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# File 'lib/nelson/expression.rb', line 11

def *(term)
  rhs_value = self.call
  lhs_value = try_to_eval term
  MultipicationExpression.new(rhs_value, lhs_value).call
end

#+(term) ⇒ Object 



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# File 'lib/nelson/expression.rb', line 17

def +(term)
  rhs_value = self.call
  lhs_value = try_to_eval term
  AdditionExpression.new(rhs_value, lhs_value).call
end

#-(term) ⇒ Object 



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# File 'lib/nelson/expression.rb', line 23

def -(term)
  rhs_value = self.call
  lhs_value = try_to_eval term
  SubtractionExpression.new(rhs_value, lhs_value).call
end