Function format_number Ruby

#number.rb
puts 'Informe um número'

number = gets.chomp

def format_number(number)

    for num in 0..number.to_i
        puts num.to_s.reverse.gsub(/(\d{3})(?=\d)/, '\\1,').reverse
    end

end

format_number(number)

def format_with_separator(number)
    whole_part, decimal_part = number.to_s.split('.')
    [whole_part.gsub(/(\d)(?=\d{3}+$)/, '\1,'), decimal_part].compact.join('.')
end

puts '--------'
puts format_with_separator(number)

puts '--------'
puts sprintf("%0.2f", number).gsub(/(\d)(?=\d{3}+\.)/, '\1,')

puts '--------'
puts sprintf("%d", number).gsub(/(\d)(?=\d{3}+$)/, '\1,')

puts '--------'
puts number.gsub(/[^\d\.]/, '')

#Use in terminal
#ruby number.rb