From: David Masover <ninja@...>
Date: 2009-03-05T16:39:02+09:00
Subject: Re: with YAML can I retrieve the class type back???

Greg Hauptmann wrote:
> Hi,
> If I wanted to persist different Ruby types (e.g. float, BigDecimal,
> integer, string) to a database based table (e.g. column names KEY and
> VALUE), if I use the "to_yaml" method to serialize their values and store
> them as strings, what's the easiest way to retrieve them back to a Ruby
> variable such that they are of the original type (i.e. not a YAML type).

If you're using Rails, there's a helper built in. For example, if your 
column named "value" is the object you want stored that way:

class Whatever <  ActiveRecord::Base
  serialize :value
  ...
end

If you want to do it yourself, use YAML.load:

serialized = my_object.to_yaml
object = YAML.load(serialized)

I have no idea if this is safe for untrusted data -- I suspect it's not. 
So, use this with your own databases, not with random web services, at 
least without putting some thought into it.