Range Parser. Transform a string in an Array of values

range_parser.rb

module Tributario
  class RangeParser
    attr_reader :range_string

    def initialize(word)
      @range_string = word
    end

    # Parse the string and return an array of numbers
    #
    # ==== Returns
    # Array[Class]
    #
    # ==== Examples
    #
    #  RangeParser.new('1-4').parse! # => [1,2,3,4]
    #  RangeParser.new('1').parse!   # => [1]
    #  RangeParser.new('1; 20-22').parse! # => [1, 20, 21, 22]
    #
    def parse!
      @range_string.split(';').collect do |number|
        numbers = number.split('-').collect { |n| Integer(n) }
        numbers = Range.new(numbers[0], numbers[1]).to_a if numbers.size == 2
        numbers
      end.flatten
    end

    # The string is valid when pass when have '-' between numbers or ';' between numbers 
    #
    # ==== Returns
    # Boolean[Class]
    #
    # ==== Examples
    #
    #  RangeParser.new('1').valid? # => true
    #  RangeParser.new('1-100').valid? # => true
    #  RangeParser.new('1; 100').valid? # => true
    #  RangeParser.new('1; 100-200').valid? # => true
    #  RangeParser.new('1- 100-200').valid? # => false
    #  RangeParser.new('1..100-200').valid? # => false
    #
    def valid?
      @range_string.gsub(' ','').split(";").all? { |str| (str.match(/^((\d+)|(\d+)-(\d+))$/) != nil) }
    end
  end
end