You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: conversions.rb
    path of file: ./repos/stackneveroverflow/vendor/bundle/ruby/2.3.0/gems/activesupport-5.0.3/lib/active_support/core_ext/numeric
    
    the code of the file until where you have to start completion: require 'active_support/core_ext/big_decimal/conversions'
require 'active_support/number_helper'
require 'active_support/core_ext/module/deprecation'

module ActiveSupport::NumericWithFormat

  # Provides options for converting numbers into formatted strings.
  # Options are provided for phone numbers, currency, percentage,
  # precision, positional notation, file size and pretty printing.
  #
  # ==== Options
  #
  # For details on which formats use which options, see ActiveSupport::NumberHelper
  #
  # ==== Examples
  #
  #  Phone Numbers:
  #  5551234.to_s(:phone)                                     # => "555-1234"
  #  1235551234.to_s(:phone)                                  # => "123-555-1234"
  #  1235551
    
  def to_s(format = nil, options = nil)
    case format
    when nil
      super()
    when Integer, String
      super(format)
    when :phone
      return ActiveSupport::NumberHelper.number_to_phone(self, options || {})
    when :currency
      return ActiveSupport::NumberHelper.number_to_currency(self, options || {})
    when :percentage
      return ActiveSupport::NumberHelper.number_to_percentage(self, options || {})
    when :delimited
      return ActiveSupport::NumberHelper.number_to_delimited(self, options || {})
    when :rounded
      return ActiveSupport::NumberHelper.number_to_rounded(self, options || {})
    when :human
      return ActiveSupport::NumberHelper.number_to_human(self, options || {})
    when :human_size
      return ActiveSupport::NumberHelper.number_to_human_size(self, options || {})
    when Symbol
      super()
    else
      super(format)
    end