0
以下所有内容在rails console（Rails 3）中都能很好地工作，除了0 ... 0的人类可读形式不是0？会导致错误的Rails'number_to_human（0）是一个错误？
irb(main):015:0> helper.number_to_human 1
=> "1"
irb(main):016:0> helper.number_to_human 2
=> "2"
irb(main):017:0> helper.number_to_human 200
=> "200"
irb(main):018:0> helper.number_to_human 3000
=> "3 Thousand"
irb(main):019:0> helper.number_to_human 30000
=> "30 Thousand"
irb(main):020:0> helper.number_to_human 300000
=> "300 Thousand"
irb(main):007:0> helper.number_to_human 1234567
=> "1.23 Million"
irb(main):008:0> helper.number_to_human 12345678
=> "12.3 Million"
irb(main):009:0> helper.number_to_human 123456789
=> "123 Million"
irb(main):010:0> helper.number_to_human 1234567890
=> "1.23 Billion"
irb(main):011:0> helper.number_to_human 12345678901
=> "12.3 Billion"
irb(main):012:0> helper.number_to_human 123456789012
=> "123 Billion"
irb(main):013:0> helper.number_to_human 123456789
=> "1.23 Trillion"
irb(main):014:0> helper.number_to_human 0
FloatDomainError: -Infinity
from c:/ruby192/lib/ruby/gems/1.9.1/gems/actionpack-3.0.0/lib/action_view/helpers/number_helper.rb:462:in `floor'
from c:/ruby192/lib/ruby/gems/1.9.1/gems/actionpack-3.0.0/lib/action_view/helpers/number_helper.rb:462:in `number_to_human'
from (irb):14
from c:/ruby192/lib/ruby/gems/1.9.1/gems/railties-3.0.0/lib/rails/commands/console.rb:44:in `start'
from c:/ruby192/lib/ruby/gems/1.9.1/gems/railties-3.0.0/lib/rails/commands/console.rb:8:in `start'
from c:/ruby192/lib/ruby/gems/1.9.1/gems/railties-3.0.0/lib/rails/commands.rb:23:in `<top (required)>'
from script/rails:6:in `require'
from script/rails:6:in `<main>'