From: Robert Klemme <bob.news@...>
Date: 2004-11-15T21:38:20+09:00
Subject: Re: OpenStruct#update ?


"Florian Gross" <flgr@ccan.de> schrieb im Newsbeitrag
news:2vrj8eF2oj365U1@uni-berlin.de...
> trans. (T. Onoma) wrote:
>
> > Sure. Okay first, basically what I was doing, given object o and data
in hash
> > h:
> >
> >     h.each do |k,v|
> >       o.instance_variable_set("@#{k}", v)
> >       o.instance_eval <<-EOS
> >         def #{k}; @#{k}; end
> >         def #{k}=(x); @#{k}=x; end
> >       EOS
> >     end
>
> h.each do |k,v|
>    class << o; self; end.send(:attr_accessor, k)
>    o.k = v
> end

Are you sure, this works?  IMHO this is more efficient:

class << o; self; end.send(:attr_accessor, *h.keys)
h.each do |k,v|
   o.send("#{k}=", v)
end

But it would be even better to check for existing methods in order to not
overwrite existing methods:

cl = class << o; self; end
im = cl.instance_methods
h.each do |k,v|
   cl.send(:attr_reader, k) unless im.include?(k.to_s)
   cl.send(:attr_writer, k) unless im.include?("#{k}=")
   o.send("#{k}=", v)
end

Kind regards

    robert