WordProblem Benchmarking

benchmark.rb

require_relative 'other_word_problem'
require_relative 'word_problem'

require 'benchmark'
TEST_COUNT = 10000


Benchmark.bmbm do |b|
  b.report("myWordy") do 
    TEST_COUNT.times do |i|
      WordProblem.new('What is 1 plus 1 plus 1?').answer
      WordProblem.new('What is 1 plus 5 minus -2?').answer
      WordProblem.new('What is 20 minus 4 minus 13?').answer
      WordProblem.new('What is 17 minus 6 plus 3?').answer
      WordProblem.new('What is 2 multiplied by -2 multiplied by 3?').answer
      WordProblem.new('What is -3 plus 7 multiplied by -2?').answer
      WordProblem.new('What is -12 divided by 2 divided by -3?').answer
    end
  end

  b.report("otherWordy") do 
    TEST_COUNT.times do |i|
      OtherWordProblem.new('What is 1 plus 1 plus 1?').answer
      OtherWordProblem.new('What is 1 plus 5 minus -2?').answer
      OtherWordProblem.new('What is 20 minus 4 minus 13?').answer
      OtherWordProblem.new('What is 17 minus 6 plus 3?').answer
      OtherWordProblem.new('What is 2 multiplied by -2 multiplied by 3?').answer
      OtherWordProblem.new('What is -3 plus 7 multiplied by -2?').answer
      OtherWordProblem.new('What is -12 divided by 2 divided by -3?').answer
    end
  end
end

file1.rb

class WordProblem
  attr_reader :text

  def initialize(text)
    @text = text
    validate_operators
    validate_numbers
  end

  def answer
    ops = operators.dup
    numbers.drop(1).reduce(numbers.first) do |a,b|
      operator = ops.shift
      calculate.fetch(operator)[a,b]
    end
  end

  OPERATORS = /plus|minus|multiplied|divided|raised/

  def operators
    @operators ||= text.scan(OPERATORS).map(&:to_sym)
  end

  def numbers
    @numbers ||= text.scan(/-?\d+/).map(&:to_i)
  end

  def calculate
    {
      :plus       => lambda { |a,b| a + b },
      :minus      => lambda { |a,b| a - b },
      :multiplied => lambda { |a,b| a * b },
      :divided    => lambda { |a,b| a / b },
      :raised     => lambda { |a,b| a **b  }
    }
  end

  private

  def validate_operators
    raise ArgumentError if operators.empty?
  end

  def validate_numbers
    raise ArgumentError if numbers.empty?
  end
end

file2.rb

require 'forwardable'

class Fixnum
  alias_method :plus, :+
  alias_method :minus, :-
  alias_method :multiplied, :*
  alias_method :divided, :/
end

class OtherWordProblem
  KNOWN_OPERATIONS = [:plus, :minus, :multiplied, :divided].freeze

  extend Forwardable
  def_delegators :Fixnum, *KNOWN_OPERATIONS

  def initialize(question)
    @question = question
    validate_operators
    validate_numbers
  end

  def answer
    numbers.drop(1).reduce(numbers.first) do |a,b|
      a.public_send(operators.shift, b)
    end
  end

  def operators
    @operators ||= question.scan(/#{operator_test}/).map(&:to_sym)
  end

  def numbers
    question.scan(/-?\d+/).map(&:to_i)
  end

  private

  attr_reader :question

  def validate_operators
    raise ArgumentError if operators.empty?
  end

  def validate_numbers
    raise ArgumentError if numbers.empty?
  end

  def operator_test
    @operator_test ||= KNOWN_OPERATIONS.join('|')
  end
end