From: "David A. Black" <dblack@...>
Date: 2008-04-26T03:25:06+09:00
Subject: Re: undefined local variable

Hi --

On Sat, 26 Apr 2008, Johan Eriksson wrote:

> Chris Hulan wrote:
>> On Apr 25, 11:16 am, Johan Eriksson <jo...@johaneriksson.se> wrote:
>>> Hi!
>>> 
>>> I have some troubles with this.
>>>
>>>            obj_as_list.each do |att|
>>>              if att[1].is_a?(String)
>>>                att[1] = "'#{att[1]'"
>> You're missing a '}' here ----------^
>> 
>> does that help?
>> 
>
> Nope. I am providing the surrounding function here. (It is defined inside a 
> class.)
>
>    def load_from_file(filename)
>      require 'yaml'
>      yaml_dict = YAML::load(File.open(filename))
>      object_list = []        #The list that should be returned
>      yaml_dict[yaml_dict.keys[0]].each do |yaml_obj|
>        new_obj = self.class.new
>        yaml_obj.each do |obj|
>          obj_as_list = obj.to_a
>          obj_as_list.each do |att|
>            if att[1].is_a?(String)
>              att[1] = "'#{att[1]}'"
>            end
>            str = "new_obj.#{att[0]} = #{att[1]}"
>            eval(str)
>          end
>        end
>        object_list << new_obj
>      end
>      object_list
>    end
>
> And the error:
>
> 	NameError: undefined local variable or method `att' for main:Object

If att[1] is, say, :att, then "#{att[1]}" is "att" and you've got a
dangling att. The whole eval thing seems extremely fragile (which eval
things usually are). I imagine there's a more robust and probably
shorter way to do this, but I'm not sure what the data coming in and
out are supposed to be like.


David

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