From: gv@... (Gerard A.W. Vreeswijk)
Date: 2004-03-03T01:19:43+09:00
Subject: dynamic assignment of instance variables

$ cat try.rb
#!/sw/bin/ruby

class Person

   attr_accessor :name, :born

   def initialize(args)
      args.each { |k, v|
         self.send "#{k}=", v
         # or: send "#{k}=", v
      }
   end

end

p Person.new( :name=> 'John', :born=>2003 )

$ try.rb
$ #<Person:0x2a67480 @born=2003, @name="John">
$ _

Wished we had something like "self.set(k, v)". Ruby ri version 1.8b
does not seem to know of such a method, at least not of a method with
such a name.

Is it possible to set instances variables without eval or string
interpolation?

Automatic accessor construction, for example, can be done without the
help of eval and without string interpolation, namely by preceding
"self.send "#{k}=", v" with

   self.class.class_eval { send :attr_accessor, k }

Thanks.