Ruby 1.8.7将哈希转换为字符串

在1.8.7,(参考：http://ruby-doc.org/core-1.8.7/Hash.html#method-i-to_s)：

Converts hsh to a string by converting the hash to an array of [ key,value ] pairs and then converting that array to a string using Array#join with the default separator.

在1.9.3,(参考：http://www.ruby-doc.org/core-1.9.3/Hash.html#method-i-to_s)

Alias for : inspect

您可以在1.8.7中对Hash类进行猴子修补,以便在本地执行以下操作：

class Hash
  alias :to_s :inspect
end

在修补猴子之前：

1.8.7 :001 > {:k => 30}.to_s
 => "k30" 
1.8.7 :002 > {:k => 30}.inspect
 => "{:k=>30}"

猴子补丁&后：

1.8.7 :003 > class Hash; alias :to_s :inspect; end
 => nil 
1.8.7 :004 > {:k => 30}.to_s
 => "{:k=>30}"