Question

这应该很简单，但它正在爆炸。有什么想法吗？

d = BigDecimal.new("2.0")
YAML::load({:a => d}.to_yaml)
TypeError: BigDecimal can't be coerced into BigDecimal
from /Users/benjohnson/.rvm/rubies/ruby-1.9.3-p125/lib/ruby/1.9.1/irb/inspector.rb:86:in `inspect'
from /Users/benjohnson/.rvm/rubies/ruby-1.9.3-p125/lib/ruby/1.9.1/irb/inspector.rb:86:in `inspect'
from /Users/benjohnson/.rvm/rubies/ruby-1.9.3-p125/lib/ruby/1.9.1/irb/inspector.rb:86:in `block in <module:IRB>'
from /Users/benjohnson/.rvm/rubies/ruby-1.9.3-p125/lib/ruby/1.9.1/irb/inspector.rb:30:in `call'
from /Users/benjohnson/.rvm/rubies/ruby-1.9.3-p125/lib/ruby/1.9.1/irb/inspector.rb:30:in `inspect_value'
from /Users/benjohnson/.rvm/rubies/ruby-1.9.3-p125/lib/ruby/1.9.1/irb/context.rb:260:in `inspect_last_value'
from /Users/benjohnson/.rvm/rubies/ruby-1.9.3-p125/lib/ruby/1.9.1/irb.rb:311:in `output_value'
from /Users/benjohnson/.rvm/rubies/ruby-1.9.3-p125/lib/ruby/1.9.1/irb.rb:160:in `block (2 levels) in eval_input'
from /Users/benjohnson/.rvm/rubies/ruby-1.9.3-p125/lib/ruby/1.9.1/irb.rb:273:in `signal_status'
from /Users/benjohnson/.rvm/rubies/ruby-1.9.3-p125/lib/ruby/1.9.1/irb.rb:156:in `block in eval_input'
from /Users/benjohnson/.rvm/rubies/ruby-1.9.3-p125/lib/ruby/1.9.1/irb/ruby-lex.rb:243:in `block (2 levels) in each_top_level_statement'
from /Users/benjohnson/.rvm/rubies/ruby-1.9.3-p125/lib/ruby/1.9.1/irb/ruby-lex.rb:229:in `loop'
from /Users/benjohnson/.rvm/rubies/ruby-1.9.3-p125/lib/ruby/1.9.1/irb/ruby-lex.rb:229:in `block in each_top_level_statement'
from /Users/benjohnson/.rvm/rubies/ruby-1.9.3-p125/lib/ruby/1.9.1/irb/ruby-lex.rb:228:in `catch'
from /Users/benjohnson/.rvm/rubies/ruby-1.9.3-p125/lib/ruby/1.9.1/irb/ruby-lex.rb:228:in `each_top_level_statement'
from /Users/benjohnson/.rvm/rubies/ruby-1.9.3-p125/lib/ruby/1.9.1/irb.rb:155:in `eval_input'
from /Users/benjohnson/.rvm/rubies/ruby-1.9.3-p125/lib/ruby/1.9.1/irb.rb:70:in `block in start'
from /Users/benjohnson/.rvm/rubies/ruby-1.9.3-p125/lib/ruby/1.9.1/irb.rb:69:in `catch'
from /Users/benjohnson/.rvm/rubies/ruby-1.9.3-p125/lib/ruby/1.9.1/irb.rb:69:in `start'
from /Users/benjohnson/.rvm/rubies/ruby-1.9.3-p125/bin/irb:16:in `<main>'Maybe IRB bug!

Answer 1

这是一个reported和fixed的错误。

最好的解决方案是升级到最新的Ruby（修补程序在补丁级别194以后）。

如果无法升级Ruby版本，可以通过安装Psych gem来解决问题。如果您这样做，则需要在gem 'psych'之前添加require 'yaml'（如果您使用的是Bundler，则将其添加到Gemfile）从gem中加载代码而不是标准库..

Answer 2

是的，我碰到过那一次。这是我所做的一个版本：

YAML & BigDecimal workaround

Answer 3

这是大卫的答案，感谢this related question更新到1.9.3中工作：

require 'yaml'
require 'bigdecimal'
YAML::ENGINE.yamler= 'syck'
class BigDecimal
  def to_yaml(opts={})
    YAML::quick_emit(object_id, opts) do |out|
      out.scalar("tag:induktiv.at,2007:BigDecimal", self.to_s)
    end
  end
end
YAML.add_domain_type("induktiv.at,2007", "BigDecimal") do |type, val|
  BigDecimal.new(val)
end
x = BigDecimal.new("2.0")
puts x.to_yaml
y = YAML.load(x.to_yaml)
puts x == y

BigDecimal不能强制转换为BigDecimal

3 个答案: