Module: RPN

Defined in:
lib/rpn_ruby.rb,
lib/rpn_ruby/version.rb

Constant Summary collapse

VERSION = 
"0.0.1"

Instance Method Summary collapse

Instance Method Details

#enter(value) ⇒ Object 



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# File 'lib/rpn_ruby.rb', line 13

def enter value
	case value
	  when '='
	  	return result
	  when '+'
	  	@stack.push @stack.pop + @stack.pop
	  when '-'
	  	subtrahend = @stack.pop
	  	@stack.push @stack.pop - subtrahend
	  when '*'
	  	@stack.push @stack.pop * @stack.pop
	  when '^'
	  	exponent = @stack.pop
	  	@stack.push @stack.pop ** exponent
	  when 'r'
	  	rt = @stack.pop
	  	@stack.push @stack.pop.root rt
	  when '/', 'd'
	  	divisor = @stack.pop
	  	@stack.push @stack.pop / divisor
	  when '%'
	  	divisor = @stack.pop
	  	@stack.push @stack.pop % divisor
	  else	
      @stack.push value.to_f
  end    
  self
rescue Exception => @err
  @stack.push 'invalid input'
  return self
end

#initialize ⇒ Object 



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# File 'lib/rpn_ruby.rb', line 9

def initialize
	@stack = []
end

#result ⇒ Object 



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# File 'lib/rpn_ruby.rb', line 45

def result
	@stack.first.to_s || ''
end